FRE-600: Implement Phase 1 WebSocket + Yjs CRDT foundation

- Create TypeScript and Vite configuration for SolidJS
- Implement Yjs document structure for screenplay collaboration
- Build WebSocket connection manager with exponential backoff reconnection
- Create CRDT document manager with undo/redo support
- Set up WebSocket sync server with JWT authentication
- Add SolidJS reactive bindings for Yjs shared types
- Build collaborative editor component
- Write unit tests for CRDT operations
- Document implementation in analysis/fre600_websocket_foundation.md

Architecture: Yjs chosen over Automerge for better ecosystem and
Tauri compatibility. WebSocket for sync, WebRTC for video.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

agents/senior-engineer/memory/2026-04-22.md

@@ -6,3 +6,19 @@
 - Inbox: empty — no assigned issues
 - No PAPERCLIP_TASK_ID or mention-based handoff
 - Exit: clean, no work to execute
+
+## Heartbeat 2
+
+- Wake reason: process_lost_retry, no task ID
+- Inbox: empty — no assigned issues
+- Exit: clean, no work to execute
+
+## Heartbeat 3 - FRE-586 Core screenplay editor
+
+- Wake reason: process_lost_retry, task: FRE-586
+- Built complete screenplay editor UI for Scripter project
+- Components: ScreenplayEditor, ElementEditor, PreviewPanel, Toolbar, StatsPanel
+- Features: 3 templates (Standard/Sitcom/Podcast), auto-formatting, keyboard shortcuts (Ctrl+0-5), Smart Enter, real-time preview, statistics panel
+- Engine: element type detection, character/scene extraction, page count estimation, word count, dialogue counts
+- Build passes, committed to master
+- Status: moved to in_review for code review pipeline