Enhance autocomplete sound system with completion feedback

- Add autocomplete_end sound event for completion confirmation
- Remove programmatic sound generation in favor of sound pack files
- Implement state tracking to prevent duplicate autocomplete sounds
- Add comprehensive sound system policy to CLAUDE.md
- Restore full CLAUDE.md documentation with development workflow
- Update Doom sound pack to include autocomplete_end.ogg mapping

Sound behavior improvements:
- Autocomplete sound plays once per session when suggestions appear
- Autocomplete_end sound plays when user selects or dismisses suggestions
- State resets cleanly for next autocomplete interaction
- Follows sound pack architecture instead of generating audio

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

CLAUDE.md

@@ -3,6 +3,10 @@
 ## Project Overview
 Bifrost is a fully accessible fediverse client built with PySide6, designed specifically for screen reader users. The application uses "post/posts" terminology instead of "toot" and focuses on excellent keyboard navigation and audio feedback.
 
+## Development Workflow
+- Check for any changes in git project before doing anything else. Make sure the latest changes have been pulled
+- See what has changed, use git commands and examine the code to make sure you are up to date with the latest code
+
 ## Core Features
 - Full ActivityPub protocol support (Pleroma and GoToSocial primary targets)
 - Threaded conversation navigation with collapsible tree view
@@ -137,6 +141,15 @@ Timeline Item: "Alice posted: Hello world (3 replies, collapsed)"
 - **collapse**: Thread collapsed
 - **success**: General success feedback
 - **error**: Error occurred
+- **autocomplete**: Autocomplete suggestions available
+- **autocomplete_end**: Autocomplete interaction ended
+
+### Sound System Policy
+- **No Sound Generation**: The application should never generate sounds programmatically
+- **Sound Pack Reliance**: All audio feedback must come from sound pack files
+- **Default Pack Requirement**: A complete default sound pack must ship with the project
+- **Themed Packs**: Users can install additional themed sound packs (like Doom)
+- If someone requests sound generation, gently remind them that all sounds should be covered by sound packs
 
 ### Sound Pack Structure
 **pack.json Format:**