Refresh Cloudflare docs and fix Queue integration

[udzura]

Summary

• refresh the general project documentation to match the current CLI and runtime architecture
• document the current Cloudflare template, request-size configuration, and platform service APIs
• fix the missing Secret host import in the Cloudflare Queue template and spike
• extend the Queue runn scenario to verify generated Wasm imports against the JavaScript host implementation
• point Queue project guidance to lib/consumer.rb

Verification

• runn run uzumibi-cli/tests/runn/new_cloudflare_queue.yml
• cargo test --package uzumibi-cli
• cargo fmt --check --package uzumibi-cli
• node --check for both Queue JavaScript hosts
• mdbook build uzumibi-docs
• Markdown relative-link check
• git diff --check