feat: add workflow resume from workspace via --workspace flag

When a workflow is interrupted (VM crash, Ctrl+C, Docker restart), it can
now be resumed by passing the workspace name. The system reads session.json
to determine which agents completed, validates deliverables exist on disk,
restores the git checkpoint, and skips already-completed agents.

- Add --workspace CLI flag and auto-terminate conflicting workflows
- Add loadResumeState, restoreGitCheckpoint, recordResumeAttempt activities
- Add skip logic for all 5 pipeline phases including parallel execution
- Separate sessionId (persistent directory) from workflowId (execution ID)
- Track resume attempts in session.json for audit trail
- Derive AgentName type from ALL_AGENTS array to eliminate duplication
- Add getDeliverablePath mapping for deliverable validation

src/audit/audit-session.ts

@@ -64,8 +64,10 @@ export class AuditSession {
   /**
    * Initialize audit session (creates directories, session.json)
    * Idempotent and race-safe
+   *
+   * @param workflowId - Optional workflow ID for tracking original or resume workflows
    */
-  async initialize(): Promise<void> {
+  async initialize(workflowId?: string): Promise<void> {
     if (this.initialized) {
       return; // Already initialized
     }
@@ -74,7 +76,7 @@ export class AuditSession {
     await initializeAuditStructure(this.sessionMetadata);
 
     // Initialize metrics tracker (loads or creates session.json)
-    await this.metricsTracker.initialize();
+    await this.metricsTracker.initialize(workflowId);
 
     // Initialize workflow logger
     await this.workflowLogger.initialize();
@@ -252,4 +254,28 @@ export class AuditSession {
     await this.ensureInitialized();
     await this.workflowLogger.logWorkflowComplete(summary);
   }
+
+  /**
+   * Add a resume attempt to the session
+   * Call this when a workflow is resuming from an existing workspace
+   *
+   * @param workflowId - The new workflow ID for this resume attempt
+   * @param terminatedWorkflows - IDs of workflows that were terminated
+   * @param checkpointHash - Git checkpoint hash that was restored
+   */
+  async addResumeAttempt(
+    workflowId: string,
+    terminatedWorkflows: string[],
+    checkpointHash?: string
+  ): Promise<void> {
+    await this.ensureInitialized();
+
+    const unlock = await sessionMutex.lock(this.sessionId);
+    try {
+      await this.metricsTracker.reload();
+      await this.metricsTracker.addResumeAttempt(workflowId, terminatedWorkflows, checkpointHash);
+    } finally {
+      unlock();
+    }
+  }
 }