Drop the scheduled run, keep the manual trigger

Operator does not want nightly or weekly runs. Pushes to main already
cover code changes, so the remaining addition is workflow_dispatch: a
manual re-run for after a credential rotation or a budget top-up,
which also retires the empty-commit trick used to pick up new secrets.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

.gitea/workflows/ci.yml

@@ -2,13 +2,6 @@ name: CI
 on:
   push:
   pull_request:
-  # Every push to main already runs this. The schedule catches what a commit
-  # cannot: the live tests depend on external state that drifts on its own —
-  # LiteLLM budget exhaustion, a model withdrawn from the proxy, a revoked
-  # Matrix or Gitea token. Nightly against the default branch surfaces that
-  # the morning it happens rather than mid-task.
-  schedule:
-    - cron: '17 6 * * *'
   # Manual re-run, e.g. after rotating a credential or raising a budget cap.
   workflow_dispatch: