feat(cli): list migrations from registered apps

[oxura]

Related issue or discussion

Closes #624

Description

cot migration list currently scans src/migrations, which means it has no way to see migrations that come from registered dependency apps. I changed the normal Cot-project path to ask the application for the list instead.

There are two parts to this:

• Cot applications now have a migration list task that registers the apps and prints every migration they expose. It stops before database setup, so listing does not need a database connection.
• cot-cli detects a runnable Cot package and delegates to that task through Cargo. The old source scan remains as a fallback for virtual workspace roots and non-runnable packages.

I also added a recursion guard for the Cot workspace itself. Without it, running the command from cot-cli could delegate back into the same binary.

As a smoke test, I generated a fresh project and ran cot migration list against it. The output included the built-in cot and cot_session migrations, neither of which exists in the project source tree.

Type of change

• Bug fix
• New feature
• Documentation
• Refactor / cleanup
• Performance improvement
• Other (describe above)

Checklist

• I've read the contributing guide
• Tests pass locally (just test-all)
• Code passes clippy (just clippy)
• Code is properly formatted (cargo fmt)
• New tests added (regression test for bugs, coverage for new features)
• Documentation (both code and site) updated (if applicable)

Local checks: the full cot package passed (1,345 tests), the cot-cli library and all migration-list unit/snapshot tests passed, and focused clippy passed with warnings denied. The full cot-cli integration run had five logging snapshot mismatches in unrelated new/migration make cases because this terminal emitted raw timestamps instead of the snapshots' filtered TIMESTAMP marker.

[codecov]

Codecov Report

❌ Patch coverage is 88.83249% with 22 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
cot-cli/src/migration_generator.rs	91.30%	5 Missing and 5 partials ⚠️
cot/src/cli.rs	82.14%	9 Missing and 1 partial ⚠️
cot-cli/src/handlers.rs	66.66%	1 Missing ⚠️
cot-cli/src/utils.rs	95.65%	1 Missing ⚠️

Flag	Coverage Δ
rust	90.11% <88.83%> (-0.11%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
cot-cli/src/handlers.rs	94.44% <66.66%> (-1.50%)	⬇️
cot-cli/src/utils.rs	94.67% <95.65%> (+0.66%)	⬆️
cot-cli/src/migration_generator.rs	89.63% <91.30%> (+0.06%)	⬆️
cot/src/cli.rs	86.35% <82.14%> (-0.99%)	⬇️

... and 4 files with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.