ci: run the v3 shared checks

[cplieger]

The CI, CodeQL and security workflows now call the v3 shared workflows (they were pinned to v2). Their header notes that Renovate bumps the pin, which holds once cplieger/.github#271 lands. ci-local: the only red is ruff EXE002 on an untouched file, a local file-mode artefact.

[github-advanced-security]

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