[Maintainer] Upgrade to v0.19.2

[github-actions]

[Maintainer] Upgrade to v0.19.2

Current version: 0.12.0
Target version: 0.19.2

Upgrade Notes

What's Changed

Other Changes

• chore: add v0.19.1 to releases.json by @ianlintner in chore: add v0.19.1 to releases.json caretaker#544
• feat(phase5): fleet lag regression harness — fleet.yml, weekly cron, caretaker fleet lag CLI by @ianlintner in feat(phase5): fleet lag regression harness — fleet.yml, weekly cron, caretaker fleet lag CLI caretaker#545

Full Changelog: ianlintner/caretaker@v0.19.1...v0.19.2

📋 Full Changelog

@copilot Please apply this upgrade.
See .github/agents/maintainer-upgrade.md for instructions.

FROM: 0.12.0
TO: 0.19.2
BREAKING: False

Steps:

1. Update version pins in pyproject.toml / requirements.txt
2. Update any workflow references
3. Run tests to verify compatibility
4. Update the version in config if applicable

Acceptance criteria:

• Version updated to target
• All tests pass
• No regressions