Remove charmbracelet/log debug statements from the file watcher that
were writing directly to stderr, corrupting the Bubble Tea terminal UI.
- Remove log.Debug calls for directory operations and file changes
- Remove log.Warn for watcher errors (silently ignore instead)
- Remove the charmbracelet/log import entirely
- Detect new subdirectory creation in the fsnotify event loop and add
it to the watcher so files created inside trigger reload events
- Handle cp -r case by checking if new directories already contain
matching files and scheduling an immediate debounced reload
- Add dirContainsMatchingFiles helper method
- Add tests for both new-subdirectory and copy-with-existing-files cases
- Add internal/watcher package with general-purpose ContentWatcher
using fsnotify, configurable file extensions, and debouncing
- Add ContentReloadEvent and App.NotifyContentReload() for TUI signaling
- Add GetPromptTemplates/GetSkillItems callback fields on AppModelOptions
following the existing GetExtensionCommands lazy-provider pattern
- Add Kit.ReloadSkills() to re-discover skills from disk
- Wire fsnotify watcher for .kit/prompts/, .kit/skills/, .agents/skills/,
and global config directories, triggering on .md/.txt changes
- TUI refreshes autocomplete entries and skill list on reload