Feat security

[dominikletica]

Summary

This is an aggregation PR for the feat-security branch tree and consists of the following child-branches:

• feat-security-planning
• feat-security-policy-docs
• feat-security-geoip-observability
• feat-security-abuse-foundation
• feat-security-admin-acl-enforcement
• feat-security-rate-enforcement
• feat-security-auto-ban
• feat-security-captcha-contract
• feat-security-icon-captcha
• feat-security-mailer-account-delivery
• feat-security-remember-me

Testing

(Note: Will be updated when this PR is marked ready-for-review.)

• bin/phpunit: [RESULT]
• bin/jstest: [RESULT]
• bin/lint: [RESULT]
• Other (if not already covered by the full suites above):

Progress

Progress will be captured in separate follow-up review comments to this PR. Use those to determine whether or not a change has already been reviewed.

Review Notes

Please review each merged PR/commit group separately.

Since merge commits were already reviewed before being merged into this branch, a light follow-up pass is sufficient: focus on obvious code-quality issues, security or privacy regressions, behavior changes, stale planning assumptions, documentation drift, missing tests, and side/cross effects caused by the combination with other merged changes.

For newly merged or not-yet-reviewed commits, perform a normal review and cover code quality, security/privacy considerations, behavioral correctness, tests, documentation consistency, branch boundaries, and worklog accuracy.

No runtime behavior is intended to change inside this aggregation PR aside from changes implemented through PR merges into this branch.

[dominikletica]

Progress

• feat-security-planning merged
• Documentation-only planning branch
• No runtime code changed
• No tests required beyond Markdown linting
• Codex Cloud Review reported no issues

[dominikletica]

Progress

• feat-security-policy-docs merged
• Documentation-only planning branch
• No runtime code changed
• No tests required beyond Markdown linting
• Codex Cloud Review reported no issues

[dominikletica]

Progress

• feat-security-rate-enforcement merged
• Feature implementation branch
• Checks passed: bin/phpunit OK, bin/jstest OK, bin/lint OK
• Codex Cloud Review reported 39 issues: 39 addressed/resolved