feat(cognee): adopt local lookup and source verification

[JTInventory]

Summary

Adopts the Cognee P1 and P2 work cleanly onto JTInventory/firstmate:main in one branch.

Included upstream-owner commits:

• P1: e6cad9807ca1399bad6eb34cdf17f0fcbd4b0dcb (feat(cognee): add local lookup manifest checker)
• P2: 07543de9c375df7e85aa51ff12a397115eb346eb (feat(cognee): verify local source hints)

This branch starts from fork/main and contains only the Cognee files from those commits. It intentionally does not include unrelated upstream-owner work such as X-mode, watcher, or no-mistakes config changes.

Files

• bin/fm-cognee-lookup.sh
• bin/fm-cognee-manifest-check.sh
• bin/fm-cognee-verify-source.sh
• docs/scripts.md
• tests/fm-cognee-lookup.test.sh
• tests/fm-cognee-source-verify.test.sh

Validation

bash -n bin/fm-cognee-lookup.sh bin/fm-cognee-manifest-check.sh bin/fm-cognee-verify-source.sh tests/fm-cognee-lookup.test.sh tests/fm-cognee-source-verify.test.sh
bash tests/fm-cognee-lookup.test.sh
bash tests/fm-cognee-source-verify.test.sh

Also attempted the full tests/*.test.sh shell sweep. It reached tests/fm-secondmate-safety.test.sh and failed on the existing fork/main behavior where fm-pr-check.sh refuses metadata with no worktree=. That failure is outside this Cognee diff.

Supersedes

This clean combined PR should supersede the earlier internal split PRs:

• feat(cognee): verify local source hints #7 (feat(cognee): verify local source hints)
• feat(cognee): add local lookup manifest checker #8 (feat(cognee): add local lookup manifest checker)

Do not merge those older PRs if this one is accepted.