docs(consumers): publish the v1 adoption golden path

[szmyty]

Outcome

Reconciles Identity's public status with the already-published v1.0.0 release and live Brand Kit, then defines the repeatable post-v1 consumer adoption path.

What changed

• records v1.0.0 as published rather than prepared;
• records the release-backed identity.egohygiene.io surface as live;
• closes the completed public-route and dogfood roadmap gates;
• adds a golden-path guide for canonical source, human approvals, immutable pins, generation, optional projections, CI drift, upgrades, and rollback;
• names Mantle feat(contract): stabilize the Identity v1 source model #27 as the first post-v1 fleet adoption while preserving Empathy and OptiFlow as release pilots.

Validation

• python3 -m unittest discover --start-directory tests --pattern "test_*.py" — 78 passed, 1 skipped
• python3 scripts/verify_docs.py — passed
• git diff --check — passed
• live https://identity.egohygiene.io/ — HTTP 200 over HTTPS

Closes #66.