Render real release notes instead of preview text on tag builds

[piotrekno1]

Follow-up to the 0.2.1 release, where the published v0.2.1 notes came out headed "Changelog preview for v0.2.1" above a blockquote promising notes that would be generated "when this is tagged" — on the tag's own release.

Cause

release.yml and release-pr.yml share scripts/build_changelog_comment.py, but the script only ever emitted the PR wording. It is not a regression: the string is byte-identical at v0.2.0.

$ git show v0.2.0:scripts/build_changelog_comment.py
        f"## Changelog preview for `{tag_name}`\n\n"
        "> Preview of the release notes that will be generated when this is tagged.\n\n"

The v0.2.0 and v0.1.5 releases read "Changelog for vX" because their bodies were hand-edited after publishing. The generator was never fixed, so every tag build has quietly required that cleanup.

Fix

release.yml sets TAG_NAME from github.ref_name; release-pr.yml never sets it. That difference already distinguishes the two callers, so main() derives preview = not TAG_NAME and build_comment() takes it as a keyword-only argument. No workflow change needed.

Verified against both real invocations on a clean clone, on Python 3.10 (which also re-confirms the tomllib removal shipped in 0.2.1):

### tag build (TAG_NAME set)     -> ## Changelog for `v0.2.1`          (no blockquote)
### PR build   (no TAG_NAME)     -> ## Changelog preview for `v0.2.1`  (blockquote kept)

Tests

First tests for this script: both wordings, the first-release range fallback, the empty-commit-range case, the release-commit filter, and that get_version() works without tomllib.

601 passed, 36 skipped; ruff check clean.

Note, not fixed here

RELEASE_COMMIT_RE only matches ^Release \d+\.\d+\.\d+$, so the subjects used by earlier releases — Bump version to 0.1.5, 0.1.4 release bump — slip through into the notes. Harmless while release commits keep the current Release X.Y.Z form; worth tightening only if that convention drifts again.

This PR also carries the 0.2.1 release commit back to devel, which was otherwise still behind main.

🤖 Generated with Claude Code

https://claude.ai/code/session_01TVrfA4Xy9wWmifB9JZc8Es

[github-actions]

Coverage report

• Total: 86% (8849/10346 lines)

Top uncovered files

• wildedge/integrations/transformers.py: 31.9% (196 lines missed)
• wildedge/integrations/mlx.py: 28.7% (122 lines missed)
• wildedge/integrations/ultralytics.py: 68.2% (82 lines missed)
• wildedge/integrations/pytorch.py: 56.9% (81 lines missed)
• wildedge/integrations/gguf.py: 62.7% (72 lines missed)