feat(providers): add OrcaRouter model catalog, LLM, and ASR support

[akf66]

Summary

• add OrcaRouter as a first-class LLM and ASR provider
• load the live OrcaRouter catalog from /v1/models and filter it by compatible endpoint capabilities
• provide a searchable model selector with OrcaRouter models prioritized and manual model IDs disabled
• route audio-capable Gemini models through OpenAI-shaped Chat Completions for transcription
• use OrcaRouter as the default channel name without overwriting custom names
• add browser-preview parity, tests, documentation, and localized UI copy

Vendor note

Thank you for maintaining OpenLess and for considering this integration.

OrcaRouter currently exposes audio input through compatible Gemini models rather than dedicated ASR models in its public catalog. We plan to add dedicated ASR models quickly, and we will update this integration as soon as those model IDs and their protocol are available.

Validation

• full Rust test suite
• npm run build
• npx tsx src/pages/settings/ProvidersSection.test.ts
• npx tsx src/pages/settings/ChannelList.test.ts
• native macOS smoke test: loaded the live model catalog, validated both OrcaRouter channels, and completed real LLM/ASR requests
• git diff --check