feat(release): simplify npm publishing

[heimanba]

Summary

• replace beta release branches with immutable CI snapshot versions derived from the Actions run and commit
• automatically start stable publishing when the Changesets release PR is merged
• retain Environment approval, npm OIDC provenance, idempotent package publishing, and post-release consumer verification
• accept npm registry responses containing a single-version array during propagation checks
• update the English and Chinese release guides

Why

The previous beta flow required preparing and managing a dedicated release branch before manually dispatching the publish workflow. Stable releases also required a second manual workflow dispatch after merging the release PR. This reduces both paths to one intentional approval while preserving the existing safety gates.

Impact

Beta releases are now dispatched once from main and receive versions such as 0.0.0-beta.run-123456789.sha-a1b2c3d. Stable publishing starts automatically after merging chore: release packages and pauses at the npm-release Environment for maintainer approval. Manual stable dispatch remains available for recovery.

Validation

• bun run typecheck:scripts
• bun test scripts/*.test.ts scripts/release/*.test.ts (57 passing)
• workflow YAML parsing
• pre-commit changed-file lint
• pre-push verification profile