Announce releases in repo and org Discussions #54

Goal

Post each release to GitHub Discussions in two places, matching what codeanalyzer-typescript now does:

• Repo-level — the existing softprops/action-gh-release publish step opens a Discussion linked to the release (category Announcements), seeded from the composed RELEASE_BODY.md. Needs the workflow permissions: to grant discussions: write.
• Org-level — a new step posts the same body into codellm-devkit/.github → Announcements via a createDiscussion GraphQL mutation, authenticated by the org-level ORG_DISCUSSIONS_TOKEN secret. It is continue-on-error so a failed org post never sinks an otherwise-good release.

Prerequisites (done)

• Discussions enabled on this repo; Announcements category exists.
• ORG_DISCUSSIONS_TOKEN org secret has repo scope (can create org discussions).

Done when

Both discussion posts appear on the next release. Patch version bump included so a release can actually exercise it.