Replace hardcoded PowerShell status hooks with stdin-forwarding hooks
that send full Claude Code hook data (tool_input, tool_response, prompt,
session_id, model, etc.) to /api/claude-hook endpoint.
- PowerShell hooks read stdin JSON and POST to /api/claude-hook
- Server derives status for backward-compat FAB animations
- Server extracts assistant_response from transcript on Stop events
- New /api/claude-permission endpoint with Promise-based allow/deny flow
- HookNotifications.vue: toast system showing session, prompt, tool use,
tool results, notifications, and final assistant response
- WebSocket broadcast for claude-hook and claude-permission message types
