docs: rewrite Chinese README, documentation, and website copy

[pandazki]

Rewrite the Chinese documentation across the repository and website using the accepted concepts-page sample as the voice reference. The Chinese README and docs index provide entry points; the site guides, concepts, architecture, protocol and extension references carry the full rewrite. Shared navigation, homepage, deployment selector and scripted demo copy follow the same terminology. docs/chinese-writing.md records the writing practice for future changes.

Reconcile the documentation with the current implementation: distinguish identity, discovery and invocation permission; include owner-created standing grants in the effective authorized view; qualify standing write and execute access, session/token lifetimes and revocation; separate shipped mesh functionality from deferred work and MCP transport support from the unfinished source-ingestion UI. Preserve executable examples, link destinations, old heading anchors and component behavior. Existing English documentation receives only corresponding factual corrections, language links and edits to embedded Chinese text.

Validation: repository gate, production VitePress build, source-coverage and technical-artifact checks, interface interpolation checks, and browser inspection of the Chinese site and selector. The application runtime is unchanged. Review the homepage wording and the complete Chinese reading path before merging.