Release package docs as 0.4.12

[ictechgy]

Summary

• bump package/plugin/marketplace version metadata to 0.4.12
• add CHANGELOG.md entry for the post-merge README/GitHub Pages copy polish now being shipped in npm package metadata

Validation

• python3 scripts/sync_plugin_copies.py --check
• python3 scripts/prepublish_check.py (741 tests)
• python3 scripts/release_smoke.py
• npm publish --dry-run --access public --tag latest
• npm view @ictechgy/context-guard@0.4.12 version --json returned E404 before publish, confirming the version is not already on npm

Release notes

Docs-only package patch so npm consumers see the same setup, packaging, helper-trust, and conservative savings-claim wording as the merged README and product site.

[ictechgy]

Ultra-review evidence for PR #222

Target commit: a46707c795447876074164007658755a3d7edfe3
Target hash: bd3ad86503a665ce8ed73d73603dd38cdc4755c3e95d3157bf0703523d492bf2
Scope: .claude-plugin/marketplace.json, CHANGELOG.md, package.json, plugins/context-guard/.claude-plugin/plugin.json

Validation

• python3 scripts/sync_plugin_copies.py --check → plugin copies synchronized
• python3 scripts/prepublish_check.py → 741 tests, OK, prepublish check: OK
• python3 scripts/release_smoke.py → release smoke: OK
• npm publish --dry-run --access public --tag latest → package preview for @ictechgy/context-guard@0.4.12, 85 files, README/README.ko.md included
• npm view @ictechgy/context-guard@0.4.12 version --json → E404 before publish, confirming no registry collision
• GitHub Actions CI run 27926377988 → pass: test-and-prepublish (3.11), test-and-prepublish (3.12), test-and-prepublish (macos-latest, 3.12)

Ultra-review tracks

• Claude: APPROVE; one MEDIUM verification item about confirming docs are in the publishable package was satisfied by npm dry-run file listing (README.md, README.ko.md, docs included).
• Codex: APPROVE; no HIGH/CRITICAL blockers.
• Antigravity: APPROVE; no findings.
• Grok: unavailable (AuthorizationRequired / empty output), excluded from consensus.
• Forge: skipped by safety gate because configured sage agent exposes network-capable fetch; excluded rather than weakening the read-only/no-network boundary.

Blocker threshold: HIGH/CRITICAL consensus. Result: 0 blockers; mergeable for release.