Type integration backend and deploy helpers

[ethayu]

Fixes #220.
Fixes #228.
Part of #201.

Summary

• Type JSON-backed build source and discovery/config response fields.
• Expose lazy integration service exports to type checkers.
• Type fleet network policies, catalog cache payloads, YAML/JSON narrowing, and deploy archive cleanup state.
• Folded Type integration deploy service #229 into this PR as a separate commit.

Verification

• Constituent focused Pyright, compile, ruff, and integration pytest checks from Type integration backend and deploy helpers #221 and Type integration deploy service #229 passed when created.
• Integrated workspace Pyright baseline after condensation: 161 files analyzed, 0 errors, 0 warnings.