This commit enhances the SearchMediaItems handler to support dual-mode
operation: unified search with filters AND autocomplete queries for
dropdown suggestions.
**Autocomplete Detection:**
- Detects autocomplete queries: author=value, genre=value, series=value, language=value
- Routes to new handleFieldValuesSearch method for dropdown population
- Returns JSON format: {"results": [{"value": "...", "count": 47, "score": 0.8}], "total": 1}
**Unified Search Integration:**
- Replaced direct DB calls (SearchMediaItems, SearchMediaItemsFuzzy) with SearchService
- Added support for all fuzzy filters: author_filter, genre_filter, series_filter, language_filter
- Added exact filters: year_min, year_max, has_cover
- Combined search query + filters in single SearchMediaItemsUnified call
- Removed fallback logic (partial → fuzzy), now single query with smart ordering
**New Method: handleFieldValuesSearch**
- Handles autocomplete queries for all field types (author, genre, series, language)
- Validates library_id requirement
- Applies default limit=50 if not specified
- Calls SearchService.SearchFieldValues() with FieldSearchParams
- Returns consistent JSON format with results array and total count
**QueryParam Handling:**
- Fixed to not use default values (Echo QueryParam only accepts single argument)
- Properly handles empty limit parameter with default fallback
- Extracts all filter parameters for unified search
**Behavior Changes:**
- SearchMediaItems no longer requires 'q' parameter (filters-only queries now valid)
- Autocomplete queries detected before filter processing (correct priority)
- Better error messages and logging
**Service Layer Pattern:**
- Follows established pattern (FiltersService, CollectionService)
- Handler is thin - extracts params and calls service
- Business logic in SearchService (created in commit 9ab2796)
**Backward Compatibility:**
- All existing query parameters still supported
- Response format unchanged for media items search
- New response format for autocomplete queries (distinct field values)
john-okeefe
b73d58b82e