Add getGitDiff() to DaemonClient + E2E tests

- Add getGitDiff(agentId) method to DaemonClient that sends git_diff_request
  and waits for git_diff_response
- Add 3 E2E tests covering:
  1. Modified file in git repo returns correct diff
  2. Clean repo returns empty diff
  3. Non-git directory returns error

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

packages/server/src/server/daemon.e2e.test.ts

@@ -1098,4 +1098,121 @@ describe("daemon E2E", () => {
       180000
     );
   });
+
+  describe("getGitDiff", () => {
+    test(
+      "returns diff for modified file in git repo",
+      async () => {
+        const cwd = tmpCwd();
+
+        // Initialize git repo
+        const { execSync } = await import("child_process");
+        execSync("git init", { cwd, stdio: "pipe" });
+        execSync("git config user.email 'test@test.com'", { cwd, stdio: "pipe" });
+        execSync("git config user.name 'Test'", { cwd, stdio: "pipe" });
+
+        // Create and commit a file
+        const testFile = path.join(cwd, "test.txt");
+        writeFileSync(testFile, "original content\n");
+        execSync("git add test.txt", { cwd, stdio: "pipe" });
+        execSync("git commit -m 'Initial commit'", { cwd, stdio: "pipe" });
+
+        // Modify the file (creates unstaged changes)
+        writeFileSync(testFile, "modified content\n");
+
+        // Create agent in the git repo
+        const agent = await ctx.client.createAgent({
+          provider: "codex",
+          cwd,
+          title: "Git Diff Test",
+        });
+
+        expect(agent.id).toBeTruthy();
+        expect(agent.status).toBe("idle");
+
+        // Get git diff
+        const result = await ctx.client.getGitDiff(agent.id);
+
+        // Verify diff returned without error
+        expect(result.error).toBeNull();
+        expect(result.diff).toBeTruthy();
+        expect(result.diff).toContain("test.txt");
+        expect(result.diff).toContain("-original content");
+        expect(result.diff).toContain("+modified content");
+
+        // Cleanup
+        await ctx.client.deleteAgent(agent.id);
+        rmSync(cwd, { recursive: true, force: true });
+      },
+      60000 // 1 minute timeout
+    );
+
+    test(
+      "returns empty diff when no changes",
+      async () => {
+        const cwd = tmpCwd();
+
+        // Initialize git repo with clean state
+        const { execSync } = await import("child_process");
+        execSync("git init", { cwd, stdio: "pipe" });
+        execSync("git config user.email 'test@test.com'", { cwd, stdio: "pipe" });
+        execSync("git config user.name 'Test'", { cwd, stdio: "pipe" });
+
+        // Create and commit a file
+        const testFile = path.join(cwd, "test.txt");
+        writeFileSync(testFile, "content\n");
+        execSync("git add test.txt", { cwd, stdio: "pipe" });
+        execSync("git commit -m 'Initial commit'", { cwd, stdio: "pipe" });
+
+        // Create agent in the git repo (no modifications)
+        const agent = await ctx.client.createAgent({
+          provider: "codex",
+          cwd,
+          title: "Git Diff Clean Test",
+        });
+
+        expect(agent.id).toBeTruthy();
+
+        // Get git diff - should be empty
+        const result = await ctx.client.getGitDiff(agent.id);
+
+        expect(result.error).toBeNull();
+        expect(result.diff).toBe("");
+
+        // Cleanup
+        await ctx.client.deleteAgent(agent.id);
+        rmSync(cwd, { recursive: true, force: true });
+      },
+      60000 // 1 minute timeout
+    );
+
+    test(
+      "returns error for non-git directory",
+      async () => {
+        const cwd = tmpCwd();
+        // Don't initialize git - just a regular directory
+
+        // Create agent in a non-git directory
+        const agent = await ctx.client.createAgent({
+          provider: "codex",
+          cwd,
+          title: "Git Diff Non-Git Test",
+        });
+
+        expect(agent.id).toBeTruthy();
+
+        // Get git diff - should return error
+        const result = await ctx.client.getGitDiff(agent.id);
+
+        expect(result.diff).toBe("");
+        expect(result.error).toBeTruthy();
+        expect(result.error).toContain("git");
+
+        // Cleanup
+        await ctx.client.deleteAgent(agent.id);
+        rmSync(cwd, { recursive: true, force: true });
+      },
+      60000 // 1 minute timeout
+    );
+  });
 });

packages/server/src/server/test-utils/daemon-client.ts

@@ -363,6 +363,32 @@ export class DaemonClient {
     this.send({ type: "set_agent_mode", agentId, modeId });
   }
 
+  // ============================================================================
+  // Git Operations
+  // ============================================================================
+
+  async getGitDiff(
+    agentId: string
+  ): Promise<{ diff: string; error: string | null }> {
+    const startPosition = this.messageQueue.length;
+
+    this.send({ type: "git_diff_request", agentId });
+
+    return this.waitFor(
+      (msg) => {
+        if (
+          msg.type === "git_diff_response" &&
+          msg.payload.agentId === agentId
+        ) {
+          return { diff: msg.payload.diff, error: msg.payload.error };
+        }
+        return null;
+      },
+      10000,
+      { skipQueueBefore: startPosition }
+    );
+  }
+
   // ============================================================================
   // Permissions
   // ============================================================================

plan.md

@@ -1174,7 +1174,7 @@ Goal: Expand DaemonClient to cover all daemon WebSocket capabilities so the app
 
   - **Done (2025-12-25 18:06)**: WHAT: Created shared `useTempClaudeConfigDir()` helper in `test-utils/claude-config.ts:22-49`, exported from `test-utils/index.ts:14`. Updated `daemon.e2e.test.ts:904-915` to add beforeAll/afterAll hooks using this helper and removed `.skip` from `describe("permission flow: Claude")`. Refactored `claude-agent.test.ts:19` to import shared helper and removed duplicate local implementation. RESULT: Both daemon Claude permission tests now pass. EVIDENCE: `npx vitest run --testNamePattern="permission flow: Claude"` shows: ✓ approves permission and executes command (8424ms), ✓ denies permission and prevents execution (7945ms). Direct `claude-agent.test.ts` permission tests also pass (4 tests). Typecheck passes.
 
-- [ ] **Implement**: Add `getGitDiff()` to DaemonClient + E2E test.
+- [x] **Implement**: Add `getGitDiff()` to DaemonClient + E2E test.
 
   **Context**: App calls `git_diff_request` to get file diffs. DaemonClient doesn't support this yet.
 
@@ -1187,6 +1187,8 @@ Goal: Expand DaemonClient to cover all daemon WebSocket capabilities so the app
   - Method returns diff content
   - E2E test passes
 
+  - **Done (2025-12-25 19:33)**: WHAT: Added `getGitDiff(agentId: string)` method to `packages/server/src/server/test-utils/daemon-client.ts:370-390`. Added 3 E2E tests in `packages/server/src/server/daemon.e2e.test.ts:1102-1217`: (1) "returns diff for modified file in git repo" - creates temp git repo, commits file, modifies it, verifies diff contains expected content; (2) "returns empty diff when no changes" - creates clean repo, verifies empty diff; (3) "returns error for non-git directory" - verifies error message for non-git cwd. RESULT: All 3 tests pass. Method returns `{diff: string, error: string | null}` matching the server's `git_diff_response` payload structure. EVIDENCE: `npm run test --workspace=@paseo/server -- daemon.e2e.test.ts -t "getGitDiff"` shows 3 passed (12 skipped).
+
 - [ ] **Implement**: Add `getGitRepoInfo()` to DaemonClient + E2E test.
 
   **Context**: App calls `git_repo_info_request` to get repo info (branch, status, etc).