chore(release): prepare v0.9.0

[minixalpha]

Development after v0.8.0 was still recorded under the released 0.8.0 development notes. Move those sections and their existing English translations into docs/dev_notes/{zh-CN,en}/0.9.x.md, preserving the experiment content and historical build versions. Keep the v0.8.0 record in 0.8.x.md and link both series from the documentation indexes.

Move the accumulated unreleased changelog into docs/changelogs/0.9.x.md as v0.9.0 dated 2026-10-05, leave a fresh empty Unreleased section, and describe the final Journal v4 schema consistently. Date the corresponding development notes. No additional user-facing changelog entry is needed for this release preparation.

Fix the release verifier to invoke --version and require the requested version: running the headless CLI with empty stdin now returns a usage error, so the previous smoke test could not verify a successful publication.

Validation:

• Verify both migrated development-note bodies are unchanged and the retained Chinese v0.8.0 source exactly matches the release tag; check all 48 local documentation links.
• Frozen core suite: 345 passed, 4 skipped. Anthropic 1.5.0 suite: 349 passed. Harbor contracts: 87 passed.
• Release verifier: Bash syntax and stubbed success, wrong-version, and command-failure cases passed.
• Build candidate wheel and sdist with version 0.9.0; both pass twine check, and the installed wheel passes --version and --help smoke checks.

Chinese and English development notes are migrated together. The top-level bilingual README and research notes are unchanged. Merge and publication of tag v0.9.0 await the maintainer confirmation required by the project skills.