Add TrustedRouter model provider

[jperla]

Summary

Add TrustedRouter as a first-class model provider in OpenWorker.

• Adds a provider card with TRUSTEDROUTER_API_KEY support and the prefilled attested API endpoint.
• Routes curated TrustedRouter aliases through the existing OpenAI-compatible provider client.
• Suggests trustedrouter/auto by default, with ZDR, E2E, cheap, and Plato options in the model picker.
• Detects sk-tr-* keys before the generic OpenAI key prefix.
• Adds the TrustedRouter mark and updates the supported-provider list.

The user-facing routed ids keep OpenWorker's existing provider-prefix convention, for example:

trustedrouter:trustedrouter/auto

OpenWorker strips the first prefix and sends trustedrouter/auto to the API.

Validation

• uv run --extra dev --extra messaging pytest -q
  • 855 passed, 1 skipped
• NODE_OPTIONS=--no-experimental-webstorage npm test
  • 68 passed
• npm run build
• npm run e2e -- onboarding.spec.ts
  • 5 passed
• Live production smoke through build_provider_client("trustedrouter", ...)
  • trustedrouter/auto returned PONG

The provider continues to use OpenWorker's existing local SecretStore; raw API keys are not returned by the settings API.

[jperla]

Rebased this onto current main and resolved the provider registry/logo conflicts while preserving the newer Meta provider entries. Local validation passes: 51 provider router/verification tests, the GUI API test, and the production GUI build.