docs: align bilingual README and retain CLI reference

[Pigbibi]

Summary

Documentation only: align the English and Simplified Chinese READMEs and move the existing detailed command examples into a linked CLI reference.

Why

The English README mixed the project overview with a long command reference, while the Chinese README omitted most setup and usage information.

Changes

• Add matching README sections, language links, local setup instructions, and configuration tables.
• Preserve all original CLI module examples in docs/cli-reference.md, organized by topic.
• Correct two artifact validation example paths and use a revision placeholder for provenance examples.

Testing

• git diff --cached --check: passed before commit.
• Python checks with MarkdownIt: Markdown fences, relative links, required section order, matching bilingual examples and options, retained CLI module examples, and privacy/style scans passed.
• Read-only list_signal_source_families --pretty and list_consumer_contracts --pretty: returned valid JSON.
• build_btc_cycle_bundle --help: every README configuration option exists.
• Organization overview and style guide targets were verified through the GitHub contents API.

The full code test suite was not run locally for this documentation-only change. The existing source CI runs automatically on the PR.

Risk and rollback

Documentation only; no code, dependency, configuration, or workflow changes. Revert the documentation commit if needed.

Breaking changes

none