fix: surface Spotify quota exhaustion

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

docs/workflow.md

@@ -17,8 +17,8 @@ below. No cloud dev environment involved.
   the repo you are reading is the mirror and shows the same history and
   the same green CI.
 - CI runs on every push: ruff, mypy and pytest for the backend; typecheck,
-  lint, build and vitest for the frontend. It has been green since the
-  first commit.
+  lint, build and vitest for the frontend. One intermediate batch exposed
+  a test typing error; the next commit fixed it, and current main is green.
 
 ## Deployment