ci: drop the Gitea mirror-sync nudge

Superseded: the Hanzo GitHub App pushes a webhook, so the forge tracks GitHub
without a per-repo workflow. This file called git.hanzo.ai/api/v1/.../mirror-sync
— a Gitea API for a system we no longer drive — and would sit inert in every repo.

One mechanism, in one place, instead of ~350 copies of a cron.

.github/workflows/sync.yml

@@ -1,29 +0,0 @@
-name: Sync to git.hanzo.ai
-# git.hanzo.ai is the CANONICAL forge. This mirror exists so links and clones
-# keep working; it does not build, test, or publish anything.
-#
-# All CI/CD lives in .hanzo/workflows and runs on the Hanzo git-runner fleet.
-# Thirteen workflows used to live here (ci, test, test-windows, quality-gate,
-# publish-pypi, …) and none of them could run: Actions is disabled at the
-# account level for the identity that pushes this repo, so a tag push produced
-# no run and `gh workflow run` returned HTTP 422. They looked like CI and were
-# not — which is how `hanzo` 0.4.4 stayed tagged-but-unpublished while PyPI kept
-# serving a build whose `auth login` cannot complete.
-#
-# This job only nudges the canonical forge to pull. If it fails, nothing is
-# broken — the forge also polls on a schedule.
-on:
-  push:
-    branches: [main]
-  workflow_dispatch: {}
-jobs:
-  nudge:
-    runs-on: ubuntu-latest
-    steps:
-      - name: Ask git.hanzo.ai to sync
-        continue-on-error: true
-        run: |
-          curl -fsS -X POST \
-            -H "Authorization: token ${{ secrets.HANZO_GIT_TOKEN }}" \
-            "https://git.hanzo.ai/api/v1/repos/hanzoai/python-sdk/mirror-sync" \
-            || echo "nudge failed — the scheduled pull will pick it up"