release: complete v1.10.13 final audit and metadata

[Regstar2]

Implements the automatable part of Issue #7 and prepares the final v1.10.13 release candidate.

Changes:

• bumps release source metadata to 1.10.13 / versionCode 51 (debug acceptance becomes 1.10.13-debug / code 52);
• aligns README RU/EN with the release candidate and canonical Regstar2/tg-ws-proxy-android URLs;
• documents Feedback and GitHub Releases update delivery in public docs;
• completes the v1.10.13 CHANGELOG scope;
• adds docs/releases/RELEASE_NOTES_v1.10.13.md;
• makes scripts/release.ps1 -Version v1.10.13 the documented canonical signed release path;
• updates the detailed release checklist for current MTProto/1443, Wi-Fi/mobile, Feedback, Updates, RU/EN and privacy checks;
• adds scripts/audit-release.ps1 for version consistency, RU/EN resource parity, obsolete repo URLs, tracked private/local files, signing/log/env material, common credential signatures and hardcoded-UI heuristics;
• runs the release audit from the normal scripts/ci.ps1 path.

This PR must not publish/tag v1.10.13. Public CI cannot validate the private signing keystore by design. After green CI, manual device acceptance and a local signed scripts/release.ps1 -Version v1.10.13 run remain release blockers.

Refs #7