📜 Scribe: Updated Technical Docs for Desktop Worker

[google-labs-jules]

🔄 Drift Detected: Addition of the worker_flutter cross-platform desktop worker which claims jobs directly via Firestore and supports offline mode.
📄 Docs Updated:docs/ARCHITECTURE.md, API.md, CONTRIBUTING.md.
💎 Note for Showcase: Mention that the README was already updated in the PR, so no new links are needed.

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PR created automatically by Jules for task 3129023431935536862 started by @TytaniumDev

[google-labs-jules]

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