feat(desktop): add inline changed-files summary

.qwen/e2e-tests/electron-desktop/conversation-changes-summary.md

@@ -0,0 +1,47 @@
+# Conversation Changed-Files Summary and Protocol Noise Cleanup
+
+- Slice date: 2026-04-26
+- Executable harness: `packages/desktop/scripts/e2e-cdp-smoke.mjs`
+- Command:
+  `cd packages/desktop && npm run e2e:cdp`
+- Result: pass
+- Artifact directory:
+  `.qwen/e2e-tests/electron-desktop/artifacts/2026-04-25T17-28-04-569Z/`
+
+## Scenario
+
+1. Launch the real Electron app with isolated HOME, runtime, user-data, and a
+   fake dirty Git workspace.
+2. Open the fake project through the desktop directory picker path.
+3. Send the first composer prompt without manually creating a thread.
+4. Approve the fake command request.
+5. Assert the main body does not expose `session-e2e-1`,
+   `Connected to session-e2e`, or `Turn complete`.
+6. Assert the conversation inline changed-files summary is visible with
+   `README.md`, `notes.txt`, `2 files changed`, `+2`, and `-1`.
+7. Open review from the inline `Review Changes` action and continue the
+   existing review, settings, and terminal smoke path.
+
+## Assertions
+
+- Protocol connection and completion events stay out of the visible
+  conversation body.
+- The changed-files summary is present before review opens and includes a
+  compact file/status/stat summary.
+- The summary opens the review drawer without replacing the conversation.
+- Console errors: 0.
+- Failed local network requests: 0.
+
+## Artifacts
+
+- `conversation-changes-summary.json`
+- `review-drawer.png`
+- `completed-workspace.png`
+- `electron.log`
+- `summary.json`
+
+## Known Uncovered Risk
+
+This harness uses deterministic fake ACP updates and a small two-file Git
+workspace. It does not yet validate long file paths, many changed files, or
+live ACP tool/file-reference payloads.