ci: remove dead release-triggered publish jobs; make RELEASING.md claims true

Review findings: RELEASING.md claimed publishing happens exclusively
from release.yml with no registry tokens, but typescript.yml and
python.yml still carried release:[published] publish jobs — never
fired (releases are created with GITHUB_TOKEN, which suppresses
workflow triggers) and unable to succeed under OIDC (typescript.yml's
still referenced the deleted NPM_TOKEN). Remove both jobs and their
release triggers; the workflows are now pure CI.

Also:
- add skip-existing to the PyPI publish action so re-runs tolerate
  already-uploaded files, and describe the per-registry guard
  accurately in RELEASING.md (npm aborts; PyPI skips)
- correct the fresh-dispatch note: same-day dispatches collide on the
  date-granular tag rather than minting a new version

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AViME1R9ES2UXT1uQDx1TG

.github/workflows/release.yml

@@ -155,6 +155,7 @@ jobs:
         uses: pypa/gh-action-pypi-publish@release/v1
         with:
           packages-dir: src/${{ matrix.package }}/dist
+          skip-existing: true # re-runs tolerate already-uploaded files
 
   publish-npm:
     needs: [update-packages, create-metadata]