docs: clarify distribution and maintenance boundaries

[ovaso]

Summary / 变更说明

• Add matching English and Simplified Chinese distribution and trust statements.
• State that public package registries are intentionally excluded and define this GitHub repository plus its Releases as the trust boundary.
• Enforce the registry-free policy in package metadata with publish = false.
• Replace fixed release-support, response-time, disclosure, backport, and platform-support promises with current validation scope and best-effort maintenance language.
• Remove wording that implied future crates.io publication.
• 新增语义一致的中英文分发与信任声明。
• 明确有意不进入公共包仓库，并以本 GitHub 仓库及其 Releases 界定信任边界。
• 在包元数据中设置 publish = false，使不向公共包仓库发布的原则得到实际约束。
• 将固定发布支持、响应时限、披露、旧版本回移和平台支持承诺改为当前验证范围与尽力维护表述。
• 删除暗示未来将发布到 crates.io 的措辞。

Validation / 验证

• cargo fmt -- --check
• cargo test --locked
• cargo clippy --all-targets --all-features -- -D warnings
• cargo build --locked --release
• Internal Markdown link targets
• GitHub YAML and Cargo TOML parsing
• Installer and shell completion syntax checks
• Relevant English and Simplified Chinese documentation and changelogs updated
• cargo publish --dry-run --locked is rejected because registry publication is disabled

Release impact / 发布影响

Documentation and package metadata only. No runtime or version change is included, and no tag or GitHub Release is required.

仅涉及文档与包元数据，不包含运行时或版本变更，也不需要创建 tag 或发布 GitHub Release。

Risk and rollback / 风险与回滚

No runtime behavior changes. Revert the documentation and package-metadata commits if this policy needs to be withdrawn.

不改变运行时行为；如需撤回该政策，回滚文档与包元数据提交即可。

[chatgpt-codex-connector]

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