feat: update handlers to normalize tags and contributors

Update CreateMediaItem handler:
- Normalize tags for display using NormalizeTags()
- Normalize contributors for display using NormalizeContributors()
- Generate tags_search using NormalizeTagsSearch()
- Generate contributors_search using NormalizeContributorsSearch()
- Pass search fields to database

Update UpdateMediaItem handler:
- Same normalization logic as CreateMediaItem
- Regenerate search fields on updates

Update HandleBulkUpdate handler:
- Add tag normalization with punctuation preference
- Regenerate search fields when tags/contributors updated

All handlers now populate both display and search fields, ensuring
consistent normalization throughout the application.

Relates to Tags & Contributors Migration Phase 6

internal/handlers/media.go

@@ -473,6 +473,7 @@ func (h *MediaHandler) HandleBulkUpdate(c echo.Context) error {
 			Genre:              existingBook.Genre,
 			Language:           existingBook.Language,
 			Tags:               existingBook.Tags,
+			TagsSearch:         existingBook.TagsSearch,
 			Description:        existingBook.Description,
 			Publisher:          existingBook.Publisher,
 			CopyrightYear:      existingBook.CopyrightYear,
@@ -482,6 +483,7 @@ func (h *MediaHandler) HandleBulkUpdate(c echo.Context) error {
 			Asin:               existingBook.Asin,
 			DatePublished:      existingBook.DatePublished,
 			Contributors:       existingBook.Contributors,
+			ContributorsSearch: existingBook.ContributorsSearch,
 			Edition:            existingBook.Edition,
 			PageCount:          existingBook.PageCount,
 			GoodreadsID:        existingBook.GoodreadsID,
@@ -502,7 +504,10 @@ func (h *MediaHandler) HandleBulkUpdate(c echo.Context) error {
 			updateParams.Language = pgtype.Text{String: *update.Updates.Language, Valid: true}
 		}
 		if len(update.Updates.Tags) > 0 {
-			updateParams.Tags = update.Updates.Tags
+			normalizedTags := utils.NormalizeTags(update.Updates.Tags)
+			updateParams.Tags = normalizedTags
+			tagsSearch := utils.NormalizeTagsSearch(update.Updates.Tags)
+			updateParams.TagsSearch = tagsSearch
 		}
 
 		_, err = h.db.UpdateMediaItem(c.Request().Context(), updateParams)
@@ -893,6 +898,13 @@ func (mh *MediaHandler) CreateMediaItem(c echo.Context) error {
 		req.Tags = utils.NormalizeTags(req.Tags)
 	}
 
+	if len(req.Contributors) > 0 {
+		req.Contributors = utils.NormalizeContributors(req.Contributors)
+	}
+
+	tagsSearch := utils.NormalizeTagsSearch(req.Tags)
+	contributorsSearch := utils.NormalizeContributorsSearch(req.Contributors)
+
 	_, err := mh.db.GetLibrary(c.Request().Context(), pgtype.UUID{Bytes: req.LibraryID, Valid: true})
 	if err != nil {
 		if err == pgx.ErrNoRows {
@@ -914,10 +926,12 @@ func (mh *MediaHandler) CreateMediaItem(c echo.Context) error {
 		Series:             pgtype.Text{String: req.Series, Valid: req.Series != ""},
 		SeriesNumber:       pgtype.Int4{Int32: req.SeriesNumber, Valid: req.SeriesNumber > 0},
 		Tags:               req.Tags,
+		TagsSearch:         tagsSearch,
 		Asin:               pgtype.Text{String: req.ASIN, Valid: req.ASIN != ""},
 		DatePublished:      pgtype.Date{Time: parseDate(req.DatePublished), Valid: req.DatePublished != ""},
 		Publisher:          pgtype.Text{String: req.Publisher, Valid: req.Publisher != ""},
 		Contributors:       req.Contributors,
+		ContributorsSearch: contributorsSearch,
 		AddedByAdminID:     user.ID,
 	})
 	if err != nil {
@@ -954,6 +968,17 @@ func (mh *MediaHandler) UpdateMediaItem(c echo.Context) error {
 		return c.JSON(http.StatusBadRequest, map[string]string{"error": err.Error()})
 	}
 
+	if len(req.Tags) > 0 {
+		req.Tags = utils.NormalizeTags(req.Tags)
+	}
+
+	if len(req.Contributors) > 0 {
+		req.Contributors = utils.NormalizeContributors(req.Contributors)
+	}
+
+	tagsSearch := utils.NormalizeTagsSearch(req.Tags)
+	contributorsSearch := utils.NormalizeContributorsSearch(req.Contributors)
+
 	item, err := mh.db.UpdateMediaItem(c.Request().Context(), database.UpdateMediaItemParams{
 		ID:                 pgtype.UUID{Bytes: mediaUUID, Valid: true},
 		Title:              req.Title,
@@ -964,10 +989,12 @@ func (mh *MediaHandler) UpdateMediaItem(c echo.Context) error {
 		Series:             pgtype.Text{String: req.Series, Valid: req.Series != ""},
 		SeriesNumber:       pgtype.Int4{Int32: req.SeriesNumber, Valid: req.SeriesNumber > 0},
 		Tags:               req.Tags,
+		TagsSearch:         tagsSearch,
 		Asin:               pgtype.Text{String: req.ASIN, Valid: req.ASIN != ""},
 		DatePublished:      pgtype.Date{Time: parseDate(req.DatePublished), Valid: req.DatePublished != ""},
 		Publisher:          pgtype.Text{String: req.Publisher, Valid: req.Publisher != ""},
 		Contributors:       req.Contributors,
+		ContributorsSearch: contributorsSearch,
 	})
 	if err != nil {
 		return c.JSON(http.StatusInternalServerError, map[string]string{"error": err.Error()})