feat: comic metadata picker, lazy-load providers, and UI improvements (#2679)

* feat: add comic metadata support to metadata picker and fix Comicvine parser

* feat: lazy-load Comicvine issue details on selection

* feat: lazy-load detail metadata for Amazon, GoodReads, and Audible parsers

* fix: prevent spurious comic_metadata row creation for non-comic books

* fix: extract rich previews from Audible search and reorder picker sections

* feat: redesign metadata editor layout with collapsible sections and boolean selects

* fix: implement per-field comic metadata locks replacing grouped locks

* feat: add comic metadata filters and fix visibleFilters backend support

* fix: use human-readable role labels in comic creator filter

* fix: auto-populate comic metadata from ComicVine during metadata fetch

* refactor: clean up ComicvineBookParser remove duplication and comments

* fix: use ComicMetadata webLink for ComicVine favicon URL

* fix: cache library options to prevent Set All dropdowns from resetting

* fix: stream book content from disk instead of loading entire file into memory

* fix: increase max visible filters from 15 to 20

* feat: replace filter multiselect with drag-and-drop reorderable list

* fix: use audiobook-specific cover paths and cache busting for audiobook thumbnail updates

* chore: enforce mandatory screenshots and stricter testing requirements in PR template

* fix: update BookServiceTest to match Resource return type after streaming change

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Co-authored-by: acx10 <acx10@users.noreply.github.com>

.github/pull_request_template.md

@@ -18,26 +18,33 @@
 
 ## 🧪 Testing
 
-<!-- What did you test? What edge cases did you cover? What could still break? -->
+<!-- MANDATORY. PRs without this filled out will be closed.
+     - What exact steps did you follow to verify the fix or feature works?
+     - How did you manually regression test existing functionality?
+     - What edge cases did you cover?
+-->
 
-## 📸 Screenshots _(if applicable)_
+## 📸 Screenshots / Video (MANDATORY)
 
-<!-- Attach screenshots or videos for UI changes -->
+> Due to an increase in untested, AI-generated PRs, we have made this section mandatory for all submissions. Please include screenshots or a screen recording that demonstrates your change working end-to-end (e.g., the bug fix in action, the new feature working, API responses, or test output for backend changes). **PRs that do not include this will be closed without review.** Thank you for helping us keep the project stable.
+
+<!-- Attach screenshots or screen recordings here -->
 
 ---
 
 ## ✅ Pre-Submission Checklist
 
-> **All boxes must be checked before requesting review.** Incomplete PRs will be closed without review, no exceptions.
+> **All boxes must be checked before requesting review.** Incomplete PRs will be closed without review. No exceptions.
 
 - [ ] Code follows project style guidelines and conventions
 - [ ] Branch is up to date with `develop` (merge conflicts resolved)
 - [ ] Automated tests added or updated to cover changes (backend **and** frontend)
 - [ ] All tests pass locally (`./gradlew test` for backend, `ng test` for frontend)
 - [ ] Changes manually verified in local dev environment (including related features)
+- [ ] Screenshots or video proving the change works are attached above **(MANDATORY)**
 - [ ] Flyway migration versioning is correct _(if schema was modified)_
 - [ ] Documentation PR submitted to [booklore-docs](https://github.com/booklore-app/booklore-docs) _(if user-facing changes)_
-- [ ] PR is reasonably scoped (PRs over 500+ changed lines will be closed, split into smaller PRs)
+- [ ] PR is reasonably scoped (PRs over 1000+ changed lines will be closed, split into smaller PRs)
 
 ### 🤖 AI-Assisted Contributions