01a0855d - Require contents write for Guard Ready mutations

[TaprootFreakAI]

EN:
dfx pr guard's GITHUB_TOKEN must have contents: write so markPullRequestReadyForReview can leave draft. HTTP 200 with unchanged isDraft is now an explicit error.

DE:
Der GITHUB_TOKEN von dfx pr guard braucht contents: write, damit markPullRequestReadyForReview den Draft aufhebt. HTTP 200 ohne Änderung an isDraft ist jetzt ein expliziter Fehler.

Details

Fork PR DFXswiss/backend#5465: Guard decided Ready, then _transition raised PR lifecycle mutation failed (HTTP 200). GraphQL with the author token set isDraft: false; the Actions token did not. The documented GitHub requirement is contents: write.

[TaprootFreakAI]

EN:
Ready after 1 review pass.
dfx pr guard's GITHUB_TOKEN must have contents: write so markPullRequestReadyForReview can leave draft.

DE:
Bereit nach 1 Review-Durchlauf.
Der GITHUB_TOKEN von dfx pr guard braucht contents: write, damit markPullRequestReadyForReview den Draft aufhebt.

Details

Head 5443b8ffdf67f714af5e7ecbc8107b036478b9d5 rebased onto current develop (incl. agent#93 REST draft re-read). Mergeable. Pytest SUCCESS (GitHub run 34619139731). Lifecycle tests 77 passed on the build host.

Comment gate: this wrap-up only. No review threads.

HTTP 200 with unchanged isDraft is an explicit error naming contents: write. GraphQL error messages are included. REST confirmation after GraphQL success remains.

Codex quality noted a missing period on the tip commit subject (pre-existing on the previously ready #92; rebase kept it). Codex logic noted falsey empty errors objects; GitHub sends a non-empty array, already fail-closed. Neither counted.