feat(FN-5358): add smart pull API route with stash conflict detection and r

Implements stash conflict detection and resolution with a new smart pull API route, resolution endpoints, and a dedicated conflict modal UI — backed by extended git audit taxonomy and route tests.

Fusion-Task-Id: FN-5358

packages/engine/src/__tests__/run-audit.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it } from "vitest";
 import type { TaskStore, RunAuditEventInput } from "@fusion/core";
-import { createRunAuditor, type DatabaseMutationType } from "../run-audit.js";
+import { createRunAuditor, type DatabaseMutationType, type GitMutationType } from "../run-audit.js";
 
 class AuditStoreStub {
   events: RunAuditEventInput[] = [];
@@ -88,6 +88,18 @@ describe("run-audit provisioning mutation types", () => {
     ]);
   });
 
+  it("accepts smart-pull git mutation types", async () => {
+    const store = new AuditStoreStub();
+    const auditor = createRunAuditor(store as unknown as TaskStore, { runId: "r1", agentId: "a1", taskId: "FN-5358" });
+
+    const types: GitMutationType[] = ["pull:fast-forward", "stash:pop-conflict"];
+    for (const type of types) {
+      await auditor.git({ type, target: "feature/worktree", metadata: { taskId: "FN-5358" } });
+    }
+
+    expect(store.events.map((event) => event.mutationType)).toEqual(types);
+  });
+
   it("records merge:scope:auto-widen git events", async () => {
     const store = new AuditStoreStub();
     const auditor = createRunAuditor(store as unknown as TaskStore, { runId: "r1", agentId: "a1", taskId: "FN-5226" });

packages/engine/src/run-audit.ts

@@ -228,8 +228,62 @@ export type GitMutationType =
   // reserved; refusal currently thrown pre-audit
   | "project:bootstrap-refused-linked-worktree"
   | "branch:reanchor"
+  /**
+   * Metadata shape:
+   * ```ts
+   * {
+   *   taskId?: string;
+   *   worktreePath: string;
+   *   stashSha: string;
+   *   stashLabel: string;
+   *   untrackedIncluded: true;
+   * }
+   * ```
+   */
   | "stash:push"
-  | "stash:pop";
+  /**
+   * Metadata shape:
+   * ```ts
+   * {
+   *   taskId?: string;
+   *   worktreePath: string;
+   *   stashSha: string;
+   *   stashLabel: string;
+   *   manualResolution?: boolean;
+   * }
+   * ```
+   */
+  | "stash:pop"
+  /**
+   * Metadata shape:
+   * ```ts
+   * {
+   *   taskId?: string;
+   *   worktreePath: string;
+   *   integrationBranch: string;
+   *   fromSha: string;
+   *   toSha: string;
+   *   durationMs: number;
+   *   succeeded: boolean;
+   *   error?: string;
+   * }
+   * ```
+   */
+  | "pull:fast-forward"
+  /**
+   * Metadata shape:
+   * ```ts
+   * {
+   *   taskId?: string;
+   *   worktreePath: string;
+   *   stashSha: string;
+   *   stashLabel: string;
+   *   conflictedFiles: string[];
+   *   advice: string;
+   * }
+   * ```
+   */
+  | "stash:pop-conflict";
 
 // ── Database mutation types ────────────────────────────────────────────────────