HYG-09: CHANGELOG.md is a stale, cross-repo-copied shared file [go part] #116

Split from LeanerCloud/cloud-commitments-cli#1178 (cross-component issue, monorepo split)

Evidence: Newest release is 0.9.0 (2026-03-06); the Unreleased section lists four minor
fixes while ~1400 commits landed since, including major features.

Impact: Users and operators cannot determine what changed since 0.9.0; the sparse Unreleased
section gives a false impression of low activity.

Recommendation: Backfill from merged PR titles and cut a release, or drop the CHANGELOG in
favor of GitHub releases.

Repo-specific verification (2026-09-27)

The literal "~1400 commits since 0.9.0" count no longer means anything post-split (this repo has
its own fresh git history from the split point), but the underlying problem survived the split
rather than being resolved by it:

• No repo has cut a release since the split -- gh release list and gh api .../tags are both
  empty for cloud-commitments-go (only cloud-commitments-cli carries a monorepo-final tag
  marking the split boundary). 0.9.0 (2026-03-06) is still the last real release, six-plus months
  stale.
• CHANGELOG.md in this repo is byte-for-byte identical to the one in cloud-commitments-mcp
  and cloud-commitments-platform -- it was copied verbatim to all three repos, not adapted.
  Its "Fixed" section under Unreleased includes "Remove debug console.log from frontend
  recommendation handler", which describes a frontend/ change -- but this repo
  (cloud-commitments-go) has no frontend/ directory; that change belongs to
  cloud-commitments-platform. The same misattribution repeats for other repo-specific entries.

So this repo's CHANGELOG both understates what changed (pre-split staleness, unresolved) and
misattributes what it does list (post-split copy-paste, a new problem the split introduced).

Acceptance criteria

• CHANGELOG.md in cloud-commitments-go contains only entries relevant to this repo's own
  code (pkg/, providers/), not copy-pasted entries from other repos.
• Either backfill and cut a release, or replace the curated CHANGELOG with a pointer to
  GitHub Releases -- team's call on which is cheaper to maintain going forward.