feat: sync model registry with latest Command Code models (55+ models)

[danielxxomg]

Description

Update models.json with the latest Command Code API model catalog, ensuring proper case-sensitivity for models like Qwen/Qwen3.7-Flash, Gemini 3.7, Claude Sonnet 5, etc.

Context

Upstream contribution: brent-weatherall#19 by @RigaOnTheRocks

[danielxxomg]

Resolved in commit eaca63c: updated catalog to 67 models from Command Code live registry and added runtime auto-discovery (src/models.ts) at startup with offline fallback.