v2 major tag branch is stale at v2.0.0, not tracking latest v2.x releases

[Svtter]

Problem

The v2 branch (used when consumers reference @v2) is stuck at commit a48f216 ("Bump version to 2.0.0", 2026-04-28). The latest release is v2.2.0 but the major tag branch was never updated.

This means anyone using @v2 is running v2.0.0 code missing all subsequent fixes:

Version	Fix
v2.0.2	fix(feature-missing): prevent contradictory verdict when no gaps found
v2.0.4	fix(feature-missing): prevent stale analysis on new commits via prompt + version resolution + cache key prefix
v2.0.5	feat(review): add extra-env input for custom environment variable passthrough
v2.1.0	spec-coverage action, spec-need detection fixes
v2.1.1	fix(spec-coverage): explicitly forbid git commit/push in prompt
v2.2.0	fix: enforce read-only mode via opencode permission config, feat: auto-delete error comments on failed runs

Impact

Repos using @v2 get feature-missing crashes (exit code 1) that are already fixed in v2.0.2+. I had to pin to @v2.2.0 explicitly to work around this.

Suggested Fix

1. Update the v2 branch to point to the v2.2.0 tag
2. Ensure update-major-tag.yml workflow runs on future releases to keep v2 in sync