The server broadcasts otUpdateApplied (with ops) to ALL clients including
the sender. Our bridge was treating its own echoed ops as remote ops and
re-applying them, causing text duplication (e.g. "simulatorimulator").

Rewrite OT handling to match Overleaf's ShareJS _onMessage pattern:
- ACK = no ops OR meta.source matches our publicId (own echo)
- REMOTE = ops from a different source
- ACK path calls onAck() without re-applying ops
- OtClient silently drops duplicate acks in synchronized state
- OtClient drops stale remote ops (version < current)
- Remove pendingEchos counter in favor of meta.source detection

Also: refresh MCP comment contexts on new-comment/delete-thread events,
add Overleaf reference repo to .gitignore.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Features:
- Electron + React + TypeScript app with Cosmic Latte theme
- CodeMirror 6 editor with LaTeX syntax highlighting
- PDF preview with pdf.js, zoom controls, SyncTeX double-click jump
- File tree with context menu (new/rename/delete/reveal)
- Overleaf Git clone with token auth + macOS Keychain storage
- Git pull/push sync for Overleaf projects
- Embedded terminal (xterm.js + node-pty) with Claude CLI integration
- LaTeX compilation via latexmk with auto package install detection
- Structured compile log (errors/warnings) with click-to-navigate
- Main document setting (auto-detect or right-click to set)
- Custom modal system (input/confirm/alert)
- Resizable panel layout (file tree | editor | PDF + terminal)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>