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/temporal/shared.ts

@@ -9,6 +9,16 @@ export interface PipelineInput {
   outputPath?: string;
   pipelineTestingMode?: boolean;
   workflowId?: string; // Added by client, used for audit correlation
+  resumeFromWorkspace?: string; // Workspace name to resume from
+  terminatedWorkflows?: string[]; // Workflows terminated during resume
+}
+
+export interface ResumeState {
+  workspaceName: string;
+  originalUrl: string;
+  completedAgents: string[];
+  checkpointHash: string;
+  originalWorkflowId: string;
 }
 
 export interface AgentMetrics {