- Remove control char filter in command palette input (matches other
  text inputs, fixes shift key issues)
- Create empty buffer with path when opening non-existent file from CLI
  (fackr newfile.rs now creates the file on save)

Add VSCode-style command palette accessible via Ctrl+P:
- ~30 commands across 9 categories (File, Edit, Search, Navigation,
  Selection, View, LSP, Brackets, Help)
- Fuzzy matching with scoring for consecutive and word-boundary matches
- Sleek dark theme modal with rounded corners and category tags
- Keyboard navigation (Up/Down/PageUp/PageDown/Enter/Escape)
- Proper viewport scrolling after command execution

When using Ctrl+D to select next occurrence, the viewport now scrolls
to show the most recently added cursor instead of staying on the
primary cursor. This makes multi-cursor selection more intuitive as
each new match becomes visible.

Toggle line comment (Ctrl+/):
- Language-aware commenting using syntax definitions
- Multi-line selection support (VSCode-style toggle)
- Smart indentation alignment across selected lines
- Proper undo grouping for multi-line operations

Performance optimizations:
- Content hash caching in Buffer (O(1) for unchanged files)
- Highlight state caching per line with invalidation
- Bracket match result caching at editor level
- Optimized render_line_with_syntax (stack arrays, no Vec<char>)
- Plain text search uses SIMD-optimized str::find()
- Streaming file search (BufReader instead of read_to_string)
- Fixed regex search byte-to-char position conversion

VSCode-style find/replace in status bar:
- Ctrl+F opens find, repeated Ctrl+F toggles/closes
- Ctrl+R opens replace, repeated Ctrl+R toggles/closes
- Tab switches between find and replace fields
- Enter finds next / replaces current match
- F3/Shift+F3 for next/previous match
- Alt+I toggles case insensitivity
- Alt+X toggles regex mode
- Alt+Enter replaces all matches
- Escape closes dialog

- Add fuzzy filter to fuss mode: type to jump to matching files
- Filter auto-resets after 500ms of inactivity
- Move git operations behind Alt+G prefix (git sub-mode)
- Move toggle hidden behind Alt+.
- Fix references panel row padding calculation
- Add ResetColor after panel rows to prevent color bleed
- Change code completion keybinding from Ctrl+Space to Ctrl+N

- Add Shift+F12 references panel with filtering

- Show navigable panel when multiple references found
- Arrow keys to navigate, Enter to jump, Esc to close
- Type to filter references by filename
- Panel shows relative paths with line numbers

Replace the status bar text input for LSP rename with a sleek
centered modal dialog that shows:
- "Rename Symbol" title
- "From:" with the original symbol name
- "To:" with an editable input field

The modal provides better visibility and UX for the rename operation.

- Add syntax highlighting for 30+ languages
- Add LSP client with auto-completion and diagnostics
- Add LSP server auto-install panel
- Add GitHub Actions for Windows/macOS/Linux builds
- Improve fuss mode navigation (left arrow/space collapse)
- Fix Ctrl+7 as alternative hints toggle

Add Python test files for manually testing LSP features:
- Hover, completion, diagnostics, go-to-definition
- References, rename, formatting, multi-cursor

Wire LSP functionality into the editor:
- F1: Hover information popup
- F2: Go to definition
- F3: Find references
- F4: Rename symbol
- Tab: Trigger/navigate completions
- Alt+M: Toggle LSP server manager panel

Add diagnostic rendering with underlines and gutter indicators.
Sync document changes to language servers on edit.

Add UI panel for discovering and installing language servers.
Detects missing servers based on file types and offers one-click
installation via npm, pip, cargo, or system package managers.

Add Language Server Protocol client implementation supporting:
- Process management for spawning language servers
- JSON-RPC message parsing and serialization
- Request/response callback handling
- Multi-server management per language
- Document synchronization (didOpen, didChange, didClose)
- Hover, completion, definition, references, rename requests
- Diagnostics handling via publishDiagnostics notifications

Note: workspaceFolders capability is disabled to ensure pyright
sends diagnostics immediately after didOpen.