Canonical pin for the skills upstream checkout (Phase P3 incorporation).
sha=1506c914b56e13aa336b1ab4415b31ccc3607c19branch=main
sha=1506c914b56e13aa336b1ab4415b31ccc3607c19 branch=main
Recorded 2026-09-14 (run qa-results/hxc159/pin/20260914T002406Z/).
The pin is a raw SHA on main — never a bare branch name. Per the T-P3.03
runtime signature it must remain an ANCESTOR of the live main tip
(asserted by gates/cm-submodule-pin-on-main.sh via git merge-base --is-ancestor); it trails HEAD as further task commits land and is
re-recorded whenever the conductor cuts a new verified pin.