Template changes for bookshelf page:
Cover filter (tristate button):
- Replace checkbox with 3-state button: Any (null) → Has Cover → No Cover
- Add Alpine state management for hasCoverState (true/false/null)
- Button shows dynamic icon and label based on state:
- ○ Cover: Any
- ✓ Has Cover
- ✗ No Cover
- Hidden input conditionally rendered by Alpine (x-if="hasCoverState !== null")
- Only submits "true"/"false" or not at all, never empty string
- Theme-aware styling using CSS variables and color-mix()
Filter management improvements:
- Add name="library" attribute to library select for proper form submission
- Create filter_item.templ component for rendering individual filter items
- Add Load Filter and Delete Filter buttons with Alpine event handlers
- Update save filter form to use HTMX attributes:
- hx-post, hx-target, hx-swap, hx-include for AJAX submission
- @htmx:afterRequest event for modal cleanup
This fixes issues where:
- Library wasn't being submitted with search/filter requests
- has_cover was sending empty string causing no results
- Saved filters couldn't be loaded or deleted
