release: bring main up to develop (Teller v1.12.0 backports + audit follow-up)

[constk]

Three more PRs since the v1.10.3 sync (#77):

• feat: pin-freshness audit + composite-action coverage #78 (#136 + #137 already in) — pin-freshness audit (script + workflow + 15 tests + DEVELOPMENT.md).
• feat: pre-stage CHANGELOG before release-PR workflow #79 (#168) — pre-stage CHANGELOG before release-PR workflow + DEVELOPMENT.md Creating a release section.
• docs: clarify required-context count + document solo-owner admin-merge policy #80 — audit follow-up: CONTRIBUTING.md states 21 required contexts (with the +1 informational note) and documents the solo-owner admin-merge policy.

Version 0.2.6 -> 0.2.9 across 3 PATCH bumps. CHANGELOG.md [Unreleased] will be rolled up to [0.3.0] (or whichever) when the next release tag fires.