feat(collections): smart (dynamic) collections — rules evaluated live at render

Type is DERIVED, not stored: a saved ruleset makes a collection SMART,
no rules = STATIC (stored collection_items links, unchanged behavior).
No schema change — collections.auto_assign_rules JSONB already carried
the config; user's decision 2026-10-14 (handoff: live-at-render, not
refresh-on-scan; create-time Static/Smart toggle; v1 NO hybrid).

- Rule gains an enabled flag (absent = enabled, legacy rules unaffected).
- Rule CRUD: POST/PUT(DELETE) /api/collections/:id/rules[/:ruleId] — the
  survivor dead effort of the rules-builder UI finally has real
  endpoints (rules were never editable after creation; nothing ever
  re-evaluated them). First rule converts a user collection to smart;
  removing the last reverts it to static. UpdateCollectionRulesJSON
  edits ONLY the rules doc so rule CRUD cannot clobber metadata.
- Live evaluation: candidates from GetVisibleLiveMediaForRules —
  visible-library set (family lens enforced at source) + archived IS
  NULL AND missing_scan_count = 0 — any enabled rule matches, title
  order. Zero refresh hooks by design: always current by construction.
- Membership mutations (add/remove/bulk-add) are 400 on smart — v1 no
  hybrid; collection_items.excluded stays the reserved future hook.
- Rules builder page (/collections/:id/rules) first time ever routable;
  templ whole-attribute interpolation ("{ expr }" inside a quoted attr
  value is literal text, as theme-{ user.Theme } silently proved).
- UI: create modal Static/⚡Smart cards (smart create redirects into the
  rules builder), ⚡ badge + real per-card counts on the grid (smart =
  live matches, static = stored-link count), smart detail renders
  matched books with no hand-pick actions + an Edit Rules button.
- API: GET /:id gains is_smart + live books; GET /: keeps the Android
  app's default exclusion, include_auto=true surfaces smart rows with
  live counts; TestRules previews against the SAME candidates the live
  render uses (visible + live, was raw first-1000).
- FIXED pre-existing regression from 7ce7321: static collection detail
  with NO library_id returned zero books — QueryType != '' caught user
  rows ('filter' default) and routed them to dashboard sections that
  never contain them; now only real system query types go there
  (handlers + SSR). App-visible symptom: /api/collections/:id without
  library_id came back books:[] for every static collection.

Tests: collections_smart_test.go (conversion, disabled rules, mutation
guards, revert-to-static, validation, system-collection prohibition,
include_auto semantics). Full offline integration suite PASS.

internal/database/querier.go

@@ -42,6 +42,10 @@ type Querier interface {
 	ClearMediaItemMetadataOverrides(ctx context.Context, id pgtype.UUID) error
 	CountAdmins(ctx context.Context) (int64, error)
 	CountArchivedMediaItems(ctx context.Context) (int64, error)
+	// Live item count for a STATIC collection (rule-free cards on the
+	// collections page); same live filter as GetCollectionItems, plus the
+	// future-hybrid excluded exclusion and an optional library scope.
+	CountCollectionLiveItems(ctx context.Context, arg CountCollectionLiveItemsParams) (int32, error)
 	// Count unlinked books for a device
 	CountUnlinkedBooks(ctx context.Context, deviceID pgtype.UUID) (int64, error)
 	CountUserDevices(ctx context.Context, userID pgtype.UUID) (int64, error)
@@ -358,6 +362,12 @@ type Querier interface {
 	GetUserReadingHistory(ctx context.Context, arg GetUserReadingHistoryParams) ([]GetUserReadingHistoryRow, error)
 	GetUserVisibleLibraries(ctx context.Context, userID pgtype.UUID) ([]GetUserVisibleLibrariesRow, error)
 	GetVisibleLibraryMediaCounts(ctx context.Context, userID pgtype.UUID) ([]GetVisibleLibraryMediaCountsRow, error)
+	// Smart ("dynamic") collections: rules are evaluated LIVE at render, so
+	// membership comes from the candidate book set instead of collection_items.
+	// The set is scoped to the requesting user's visible libraries (family
+	// lens enforced at the source) and live items only — the same filters the
+	// static collection paths apply.
+	GetVisibleLiveMediaForRules(ctx context.Context, arg GetVisibleLiveMediaForRulesParams) ([]MediaItems, error)
 	HasRecentConflictResolution(ctx context.Context, arg HasRecentConflictResolutionParams) (bool, error)
 	IncrementSyncQueueAttempts(ctx context.Context, arg IncrementSyncQueueAttemptsParams) (SyncQueue, error)
 	// Check if book is in collection
@@ -474,6 +484,9 @@ type Querier interface {
 	TombstoneSystemCollection(ctx context.Context, id pgtype.UUID) error
 	// Update collection
 	UpdateCollection(ctx context.Context, arg UpdateCollectionParams) (Collections, error)
+	// Replace ONLY the auto_assign_rules document (rule CRUD: read-modify-write
+	// of the JSONB without touching metadata stale clients did not send).
+	UpdateCollectionRulesJSON(ctx context.Context, arg UpdateCollectionRulesJSONParams) (Collections, error)
 	UpdateDashboardPreferences(ctx context.Context, arg UpdateDashboardPreferencesParams) (UserDashboardPreferences, error)
 	UpdateDevice(ctx context.Context, arg UpdateDeviceParams) (Devices, error)
 	UpdateDeviceAuthToken(ctx context.Context, arg UpdateDeviceAuthTokenParams) (Devices, error)

internal/database/queries.sql.go

@@ -293,6 +293,31 @@ func (q *Queries) CountArchivedMediaItems(ctx context.Context) (int64, error) {
 	return count, err
 }
 
+const CountCollectionLiveItems = `-- name: CountCollectionLiveItems :one
+SELECT COUNT(*)::int FROM collection_items ci
+JOIN media_items mi ON ci.media_item_id = mi.id
+WHERE ci.collection_id = $1
+  AND NOT COALESCE(ci.excluded, false)
+  AND ($2::uuid IS NULL OR mi.library_id = $2::uuid)
+  AND mi.archived_at IS NULL
+  AND mi.missing_scan_count = 0
+`
+
+type CountCollectionLiveItemsParams struct {
+	CollectionID pgtype.UUID `db:"collection_id" json:"collection_id"`
+	LibraryID    pgtype.UUID `db:"library_id" json:"library_id"`
+}
+
+// Live item count for a STATIC collection (rule-free cards on the
+// collections page); same live filter as GetCollectionItems, plus the
+// future-hybrid excluded exclusion and an optional library scope.
+func (q *Queries) CountCollectionLiveItems(ctx context.Context, arg CountCollectionLiveItemsParams) (int32, error) {
+	row := q.db.QueryRow(ctx, CountCollectionLiveItems, arg.CollectionID, arg.LibraryID)
+	var column_1 int32
+	err := row.Scan(&column_1)
+	return column_1, err
+}
+
 const CountUnlinkedBooks = `-- name: CountUnlinkedBooks :one
 SELECT COUNT(*) as count
 FROM unlinked_books
@@ -8512,6 +8537,110 @@ func (q *Queries) GetVisibleLibraryMediaCounts(ctx context.Context, userID pgtyp
 	return items, nil
 }
 
+const GetVisibleLiveMediaForRules = `-- name: GetVisibleLiveMediaForRules :many
+SELECT mi.id, mi.library_id, mi.title, mi.author, mi.isbn, mi.description, mi.file_path, mi.file_size, mi.mime_type, mi.cover_image_path, mi.series, mi.series_number, mi.tags, mi.asin, mi.date_published, mi.publisher, mi.contributors, mi.language, mi.edition, mi.page_count, mi.genre, mi.copyright_year, mi.goodreads_id, mi.openlibrary_id, mi.google_books_id, mi.added_by_admin_id, mi.created_at, mi.imported_at, mi.updated_at, mi.format_group, mi.format_mimetype, mi.is_reflowable, mi.has_fixed_layout, mi.total_characters, mi.chapter_count, mi.entitlement_id, mi.revision_number, mi.kobo_content_id, mi.kobo_metadata, mi.manga_type, mi.reading_direction, mi.series_count, mi.volume, mi.imprint, mi.age_rating, mi.web_url, mi.story_arc, mi.is_black_and_white, mi.metadata_notes, mi.community_rating, mi.alternate_info, mi.scan_information, mi.summary, mi.metadata_overrides, mi.missing_scan_count, mi.archived_at, mi.chapter_metadata, mi.library_type_name, mi.tags_search, mi.contributors_search, mi.file_sha256, mi.opf_identifier, mi.opf_uuid, mi.hash_confidence FROM media_items mi
+WHERE ($1::uuid IS NULL OR mi.library_id = $1::uuid)
+  AND ($2::uuid[] IS NULL OR mi.library_id = ANY($2::uuid[]))
+  AND mi.archived_at IS NULL
+  AND mi.missing_scan_count = 0
+ORDER BY mi.title ASC
+`
+
+type GetVisibleLiveMediaForRulesParams struct {
+	LibraryID         pgtype.UUID   `db:"library_id" json:"library_id"`
+	VisibleLibraryIds []pgtype.UUID `db:"visible_library_ids" json:"visible_library_ids"`
+}
+
+// Smart ("dynamic") collections: rules are evaluated LIVE at render, so
+// membership comes from the candidate book set instead of collection_items.
+// The set is scoped to the requesting user's visible libraries (family
+// lens enforced at the source) and live items only — the same filters the
+// static collection paths apply.
+func (q *Queries) GetVisibleLiveMediaForRules(ctx context.Context, arg GetVisibleLiveMediaForRulesParams) ([]MediaItems, error) {
+	rows, err := q.db.Query(ctx, GetVisibleLiveMediaForRules, arg.LibraryID, arg.VisibleLibraryIds)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	items := []MediaItems{}
+	for rows.Next() {
+		var i MediaItems
+		if err := rows.Scan(
+			&i.ID,
+			&i.LibraryID,
+			&i.Title,
+			&i.Author,
+			&i.Isbn,
+			&i.Description,
+			&i.FilePath,
+			&i.FileSize,
+			&i.MimeType,
+			&i.CoverImagePath,
+			&i.Series,
+			&i.SeriesNumber,
+			&i.Tags,
+			&i.Asin,
+			&i.DatePublished,
+			&i.Publisher,
+			&i.Contributors,
+			&i.Language,
+			&i.Edition,
+			&i.PageCount,
+			&i.Genre,
+			&i.CopyrightYear,
+			&i.GoodreadsID,
+			&i.OpenlibraryID,
+			&i.GoogleBooksID,
+			&i.AddedByAdminID,
+			&i.CreatedAt,
+			&i.ImportedAt,
+			&i.UpdatedAt,
+			&i.FormatGroup,
+			&i.FormatMimetype,
+			&i.IsReflowable,
+			&i.HasFixedLayout,
+			&i.TotalCharacters,
+			&i.ChapterCount,
+			&i.EntitlementID,
+			&i.RevisionNumber,
+			&i.KoboContentID,
+			&i.KoboMetadata,
+			&i.MangaType,
+			&i.ReadingDirection,
+			&i.SeriesCount,
+			&i.Volume,
+			&i.Imprint,
+			&i.AgeRating,
+			&i.WebUrl,
+			&i.StoryArc,
+			&i.IsBlackAndWhite,
+			&i.MetadataNotes,
+			&i.CommunityRating,
+			&i.AlternateInfo,
+			&i.ScanInformation,
+			&i.Summary,
+			&i.MetadataOverrides,
+			&i.MissingScanCount,
+			&i.ArchivedAt,
+			&i.ChapterMetadata,
+			&i.LibraryTypeName,
+			&i.TagsSearch,
+			&i.ContributorsSearch,
+			&i.FileSha256,
+			&i.OpfIdentifier,
+			&i.OpfUuid,
+			&i.HashConfidence,
+		); err != nil {
+			return nil, err
+		}
+		items = append(items, i)
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+	return items, nil
+}
+
 const HasRecentConflictResolution = `-- name: HasRecentConflictResolution :one
 SELECT EXISTS(
     SELECT 1 FROM sync_conflicts
@@ -12383,6 +12512,39 @@ func (q *Queries) UpdateCollection(ctx context.Context, arg UpdateCollectionPara
 	return i, err
 }
 
+const UpdateCollectionRulesJSON = `-- name: UpdateCollectionRulesJSON :one
+UPDATE collections SET auto_assign_rules = $2 WHERE id = $1 RETURNING id, user_id, name, description, color, icon, auto_assign_rules, view_settings, show_on_dashboard, query_type, priority, is_system_collection, created_at, deleted_at
+`
+
+type UpdateCollectionRulesJSONParams struct {
+	ID              pgtype.UUID `db:"id" json:"id"`
+	AutoAssignRules []byte      `db:"auto_assign_rules" json:"auto_assign_rules"`
+}
+
+// Replace ONLY the auto_assign_rules document (rule CRUD: read-modify-write
+// of the JSONB without touching metadata stale clients did not send).
+func (q *Queries) UpdateCollectionRulesJSON(ctx context.Context, arg UpdateCollectionRulesJSONParams) (Collections, error) {
+	row := q.db.QueryRow(ctx, UpdateCollectionRulesJSON, arg.ID, arg.AutoAssignRules)
+	var i Collections
+	err := row.Scan(
+		&i.ID,
+		&i.UserID,
+		&i.Name,
+		&i.Description,
+		&i.Color,
+		&i.Icon,
+		&i.AutoAssignRules,
+		&i.ViewSettings,
+		&i.ShowOnDashboard,
+		&i.QueryType,
+		&i.Priority,
+		&i.IsSystemCollection,
+		&i.CreatedAt,
+		&i.DeletedAt,
+	)
+	return i, err
+}
+
 const UpdateDashboardPreferences = `-- name: UpdateDashboardPreferences :one
 UPDATE user_dashboard_preferences
 SET hidden_collections = $2,

internal/database/queries/queries.sql

@@ -2190,6 +2190,11 @@ SET
 WHERE id = $1
 RETURNING *;
 
+-- Replace ONLY the auto_assign_rules document (rule CRUD: read-modify-write
+-- of the JSONB without touching metadata stale clients did not send).
+-- name: UpdateCollectionRulesJSON :one
+UPDATE collections SET auto_assign_rules = $2 WHERE id = $1 RETURNING *;
+
 -- Delete collection
 -- name: DeleteCollection :exec
 DELETE FROM collections WHERE id = $1;
@@ -2628,6 +2633,31 @@ WHERE ci.collection_id = sqlc.narg('collection_id')
 ORDER BY ci.added_at DESC
 LIMIT sqlc.narg('limit');
 
+-- Smart ("dynamic") collections: rules are evaluated LIVE at render, so
+-- membership comes from the candidate book set instead of collection_items.
+-- The set is scoped to the requesting user's visible libraries (family
+-- lens enforced at the source) and live items only — the same filters the
+-- static collection paths apply.
+-- name: GetVisibleLiveMediaForRules :many
+SELECT mi.* FROM media_items mi
+WHERE (sqlc.narg('library_id')::uuid IS NULL OR mi.library_id = sqlc.narg('library_id')::uuid)
+  AND (sqlc.narg('visible_library_ids')::uuid[] IS NULL OR mi.library_id = ANY(sqlc.narg('visible_library_ids')::uuid[]))
+  AND mi.archived_at IS NULL
+  AND mi.missing_scan_count = 0
+ORDER BY mi.title ASC;
+
+-- Live item count for a STATIC collection (rule-free cards on the
+-- collections page); same live filter as GetCollectionItems, plus the
+-- future-hybrid excluded exclusion and an optional library scope.
+-- name: CountCollectionLiveItems :one
+SELECT COUNT(*)::int FROM collection_items ci
+JOIN media_items mi ON ci.media_item_id = mi.id
+WHERE ci.collection_id = $1
+  AND NOT COALESCE(ci.excluded, false)
+  AND (sqlc.narg('library_id')::uuid IS NULL OR mi.library_id = sqlc.narg('library_id')::uuid)
+  AND mi.archived_at IS NULL
+  AND mi.missing_scan_count = 0;
+
 -- name: GetLibraryItems :many
 SELECT mi.* FROM media_items mi
 WHERE (sqlc.narg('library_id')::uuid IS NULL OR mi.library_id = sqlc.narg('library_id')::uuid)