fix: project-scope terminal, file browser, agent execution, and heartbeat monitor

- TerminalService: use per-project instance map instead of destructive singleton
- File browser: thread projectId through API functions, hooks, and components
- Workspace file editor: pass projectId to read/write operations
- Agent heartbeat: guard execution with project scope validation
- Agent runs/stop: validate heartbeatMonitor matches scoped project
- CLI dashboard/serve: pass rootDir to heartbeatMonitor via server options
- Add getRootDir() to HeartbeatMonitor for scope comparison

Co-authored-by: factory-droid[bot] <138933559+factory-droid[bot]@users.noreply.github.com>

packages/cli/src/commands/dashboard.ts

@@ -956,7 +956,14 @@ export async function runDashboard(port: number, opts: { paused?: boolean; dev?:
     automationStore,
     missionAutopilot,
     missionExecutionLoop,
-    heartbeatMonitor,
+    heartbeatMonitor: heartbeatMonitor
+      ? {
+          rootDir: cwd,
+          startRun: heartbeatMonitor.startRun.bind(heartbeatMonitor),
+          executeHeartbeat: heartbeatMonitor.executeHeartbeat.bind(heartbeatMonitor),
+          stopRun: heartbeatMonitor.stopRun.bind(heartbeatMonitor),
+        }
+      : undefined,
     pluginStore,
     pluginLoader,
     pluginRunner: pluginLoader,

packages/cli/src/commands/serve.ts

@@ -768,7 +768,14 @@ export async function runServe(
     automationStore,
     missionAutopilot,
     missionExecutionLoop,
-    heartbeatMonitor,
+    heartbeatMonitor: heartbeatMonitor
+      ? {
+          rootDir: cwd,
+          startRun: heartbeatMonitor.startRun.bind(heartbeatMonitor),
+          executeHeartbeat: heartbeatMonitor.executeHeartbeat.bind(heartbeatMonitor),
+          stopRun: heartbeatMonitor.stopRun.bind(heartbeatMonitor),
+        }
+      : undefined,
     pluginStore,
     pluginLoader,
     pluginRunner: pluginLoader,