Align Go and Python initialization on the new storage baseline

[gurnben]

Summary

• Generate format, revision, and baseline constants from canonical contracts metadata so Go and Python initialize compatible revision-one databases without hand-maintained version drift.
• Reject incompatible or unstamped existing stores, protect SQLite connections from temporary-object shadowing, and add bidirectional interoperability tests. Prepare Go SDK 0.15.0; preserve the merged report-finding projection fix.

Dependency and rollout

Depends on traust-security/traust-contracts#7 and pins its exact commit 7cb54f28297860c1c1bd5d498fbeb0a5dcd5fdc0. Merge contracts first. If that commit is rewritten, update the pin and regenerate before merging this PR.

Existing stores require an explicit rebuild/re-import or reviewed migration. No database is dropped, migrated, or relabeled automatically. Fence old clients before resetting storage. The baseline identifier distinguishes compatibility epochs; it is not a full schema-integrity proof.

Most generated type changes are contracts provenance headers, not artifact schema changes.

Validation

• 130 Go tests passed with real PostgreSQL 16 and matching Python contracts; two optional live-corpus tests skipped.
• Python-to-Go and Go-to-Python initialization passed on SQLite and PostgreSQL, including populated report persistence.
• Full race suite, lint, govulncheck, gosec, deterministic generation/check-drift, and release metadata gate passed.
• No SCI or live infrastructure changes.

💘 Generated with Crush