fix(mcp): recover orphaned sessions and preserve multimodal results

[xiyuren5-beep]

Summary

• add project-level list_edit_sessions and recover_edit_session tools
• preserve disconnected drafts as recoverable orphans instead of silently discarding them
• keep strict revision checks and prevent active-owner takeover
• return structured active-session conflicts without leaking private session IDs
• expose explicit real-tool confirmation IDs and pending status in the UI
• preserve MCP ImageContent before artifact sanitization

Safety

• resume is allowed only when the orphan checkpoint matches the current project revision
• revision-mismatched drafts can only be discarded
• competing live transports cannot claim another owner's session
• parameter-bound one-shot confirmations remain unchanged

Verification

• TypeScript project build
• Vite production build
• Electron main-process build
• external edit-session runtime verification
• external draft persistence and reload verification
• MCP structured image-content verification
• broker binding and cancellation verification