Add metadata-only bundle inspection and fast registry lookup

[iskandr]

Summary

Closes #88.

• Add verify_files=False to bundle inspection and install cache-hit checks.
• Fast checks validate ownership, one generation's pointer/receipt, source expectations, required inventory, regular readable files, and recorded sizes without reading payload contents.
• Fast bundle and per-file results always report verified=False; same-size corruption still requires full checks.
• Make registry local_path, is_cached, and status metadata-only by default; explicit inspection and install cache-hit defaults remain full verification.
• New acquisitions and explicit recovery always validate bytes before pointer publication, regardless of the cache-hit setting.
• Update API docs, trust/cost guidance, changelog, and version to 1.17.0.

Verification

• 831 tests pass; 93% coverage.
• Ruff and git diff --check pass.
• Both offline examples pass.
• New regressions cover forbidden payload reads/writes/network, read-only stores, same-size corruption, unsafe paths/types, malformed metadata, identity mismatch, permission errors, recovery/publication validation, and concurrent refresh snapshots.

This PR is not merged or published.

[coveralls]

Coverage Report for CI Build 36963256981

Coverage increased (+0.2%) to 93.349%

Details

• Coverage increased (+0.2%) from the base build.
• Patch coverage: 29 of 29 lines across 2 files are fully covered (100%).
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	2601
Covered Lines:	2428
Line Coverage:	93.35%
Coverage Strength:	7.46 hits per line

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💛 - Coveralls