agent-platform release v4.66.6

The dev channel reads gitsemver 3’s tag shape: a branch’s builds are X.Y.Z-r<branch-hash>t<YYYYMMDDHHMMSS>h<sha7>, selected with ^.*-r<branch-hash>t[0-9]{14}h[0-9a-f]{7}$ (giantswarm/architect-orb 10.10.0). Both charts, the kagent line and the Substrate line publish dev builds in that shape since 2026-09-23 (gitsemver branch-hash <branch> prints the hash, 588f3d76 for the lines’ branch giantswarm); a filter for the superseded X.Y.Z-dev.<branch>.<date>.<time>.h<sha7> shape matches no new build. The defaults carry no filter and the stable ranges no -0, so a release refuses a dev build of either shape (tests/verify-kagent-wiring.py asserts it for the current shape too); the BOM check accepts an exact pin of either shape, and verify-labels renders both charts at a current dev version as well. README “Dev channel”, UPGRADE.md.