* ci(circleci): clone the public repo over HTTPS so main jobs stop failing at checkout
The project's SSH checkout key stopped authenticating on Oct 27, so every job's built-in checkout step failed with Permission denied (publickey). The repo is public, so each job now fetches its pipeline's commit anonymously over HTTPS, the way the migration jobs already did
* fix(circleci): let the PR path filter read history after the shallow clone and test the clone step itself
* fix(circleci): clone full history without file contents, retry the fetch, and record the integration schedule
The depth-1 clone left the PR path filter without a merge base, and the unshallow that fixed it pulled about 1.4 GB per filtered job. A blobless fetch gives every job the history the built-in checkout step gave, so the path filter change goes back to main's version. The fetch now gets three tries, the tests run the step under the Windows job's bare bash too, and .circleci/AGENTS.md records the integration schedule's cron
* fix(circleci): stop on the fetch error once the three tries run out, and name the GitHub App fallback as the cause
* fix(circleci): retry the checkout's file download with the fetch, since a dropped download failed the job outside the retry
* fix(circleci): fetch the routing parity base with its file contents, since the blobless clone downloaded each file separately
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Co-authored-by: mateo-berri <277851410+mateo-berri@users.noreply.github.com>
