Update CLAUDE.md with completed features

- Replace implementation plan with feature documentation
- Document all keybindings
- Add technical details about MPV IPC
- List UI layout structure
- Mark all phases as complete

CLAUDE.md

@@ -38,40 +38,40 @@ paths = [
 4. Playback uses cached file paths
 5. Rescan command/keybinding to refresh cache
 
-### Implementation Plan
+## Features
 
-**Phase 1: Foundation + Cache System (CRITICAL)**
-- Create Cargo.toml with dependencies (ratatui, crossterm, libmpv-rs, tokio, serde)
-- Set up cache directory structure (XDG_CACHE_HOME/cm-player/)
-- Implement cache serialization/deserialization
-- File metadata cache schema (path, size, duration, codec, hash)
-- Config file parsing (scan paths)
-- Basic TUI two-panel layout
-- State management with cache integration
+### Core Functionality
+- **Cache-Only Operation** - Browse media from cached file structure, no direct filesystem access
+- **MPV Integration** - Playback via MPV IPC (subprocess), no library linking required
+- **Playlist Management** - Play single files, entire directories, or marked files
+- **File Marking** - Mark multiple files to create custom playlists
+- **Tree Navigation** - Vim-style keybindings for browsing collapsible directory structure
+- **Manual Library Refresh** - User-controlled scanning with 'r' key
 
-**Phase 2: File Scanner with Caching**
-- Directory traversal with media filtering (.mp3, .mp4, .mkv, .flac, etc.)
-- Write all metadata to cache immediately
-- Load from cache on startup (instant)
-- Background refresh/validation
-- Display cached structure in left panel with tree navigation
+### UI Layout (cm-dashboard style)
+- **Title Bar** - Shows player state (Playing/Paused/Stopped/Refreshing)
+- **Left Panel** - Cached media file tree with vim navigation
+- **Right Panel** - Player info (progress, volume) + Playlist view
+- **Status Bar** - Centered help text with all keybindings
 
-**Phase 3: MPV Integration**
-- Initialize libmpv
-- Playback from cached file paths
-- Status display in right panel
-- Event handling (position, duration, state)
+### Keybindings
+- `j/k` or `↑↓` - Navigate files
+- `h/l` - Collapse/expand directories
+- `t` - Mark/unmark file
+- `c` - Clear all marks
+- `Enter` - Play (priority: marked files > directory > single file)
+- `Space` - Pause/resume
+- `← →` - Seek backward/forward 10 seconds
+- `+ -` - Volume up/down by 5%
+- `n/p` - Next/previous track in playlist
+- `r` - Rescan library (manual refresh)
+- `q` - Quit
 
-**Phase 4: Player Controls**
-- Keyboard shortcuts (space: pause, q: quit, arrows: navigate/seek, r: rescan)
-- Volume control
-- Progress bar
-- Playlist/queue (cached)
-
-**Phase 5: Polish**
-- Error handling
-- Bandwidth optimization validation
-- CI integration with release workflow
+### Technical Details
+- **MPV IPC** - Communicates with mpv via Unix socket and JSON protocol
+- **No Version Lock** - Uses mpv binary, not libmpv library (avoids version mismatch)
+- **Logging** - Redirected to `/tmp/cm-player.log` to avoid TUI interference
+- **Auto-advance** - Automatically plays next track when current ends
 
 ## Automated Binary Release System