feat(image-generator): refresh provider model catalogs and validate requests - #9653

Summary

• Refresh the Image Generator catalogs with 178 fal endpoints, current OpenAI image models, and stable Google Nano Banana models, preserving supported saved model aliases.
• Share model capabilities between the picker and request builder; validate settings before generation and keep the tool output to one image.
• Secure fal queue polling and retain completed-generation billing receipts in structured logs and Copilot reconciliation through delivery failures. Record the two added client-safe catalog modules in the boundary baseline.

Type of Change

• Feature and bug fix

Testing

• Validated 2,782 request variants for all 178 fal endpoints against their live OpenAPI schemas through the block and tool input path; checked native provider settings against official documentation. No paid inference jobs were submitted.
• Regression tests reproduced foreign queue URL, nested endpoint, unknown model, and completion receipt failures before the fixes; all focused provider and workflow state regression tests pass.
• Root test suite passes (39,434 app tests), all 29 workspace type checks, lint, all 62 audits, block registry audit, and generated artifact checks pass.

Checklist

• Code follows project style guidelines
• Self-reviewed my changes
• Tests added/updated and passing (new tests pass the test-audit authoring gate)
• No new warnings introduced
• I confirm that I have read and agree to the terms outlined in the Contributor License Agreement (CLA)