feat: initial public release

ConsentOS — a privacy-first cookie consent management platform.

Self-hosted, source-available alternative to OneTrust, Cookiebot, and
CookieYes. Full standards coverage (IAB TCF v2.2, GPP v1, Google
Consent Mode v2, GPC, Shopify Customer Privacy API), multi-tenant
architecture with role-based access, configuration cascade
(system → org → group → site → region), dark-pattern detection in
the scanner, and a tamper-evident consent record audit trail.

This is the initial public release. Prior development history is
retained internally.

See README.md for the feature list, architecture overview, and
quick-start instructions. Licensed under the Elastic Licence 2.0 —
self-host freely; do not resell as a managed service.

.github/PULL_REQUEST_TEMPLATE.md

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+## Summary
+
+<!-- Brief description of what this PR does and why -->
+
+## Changes
+
+-
+
+## Test plan
+
+- [ ] Tests added/updated
+- [ ] `make check` passes locally
+- [ ] Manual testing done (if applicable)
+
+## Related issues
+
+<!-- Link any related issues: Fixes #123, Relates to #456 -->