chore: prepare v0.4.4 release

[ovaso]

Summary / 变更说明

• Finalize the current Unreleased entries as version 0.4.4.
• Update the Cargo package/lockfile version and both README version markers.
• No CLI, manifest, automation protocol, Git safety boundary, or scheduler behavior changes.

Validation / 验证

• cargo fmt -- --check
• cargo test --locked
• cargo clippy --all-targets --all-features -- -D warnings
• cargo build --locked --release
• Default-disabled check, tests, Clippy, and release build
• cargo deny --offline check advisories bans licenses sources
• Cargo metadata reports 0.4.4
• YAML parsing, Markdown relative links, and git diff --check
• English and Simplified Chinese README/changelog updates are synchronized

Risk and rollback / 风险与回滚

Version metadata and release notes only. Roll back by reverting the squash merge before creating the v0.4.4 tag.

[ovaso]

@codex review

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 941b34859e

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".