Why: v0.2.0 is the hard prerequisite for RDM shared work, and the release
checklist referenced a stale SurfaceVersion and tag message.
Evidence: SELF - scope lines are tied to merged Backend PRs (#66-#110);
Backend #110 CI success; UI composite run 1369 shows 14 files/103 tests.
Impact: Adds docs/records/2026-10-09-base-v0.2.0-release.md and points the
compat policy and the EXT-1 proposal at the actual 2.5.0-experimental line.
Tag creation and push stay with the owner (dual-key rule).
Refs: Dev feature/base-v020-release; Backend #110
weichen
176db44c4b