- extra_headers participates in the section-3 group identity (mirrors
section 4 — header-routed tenants behind one proxy URL stay distinct)
- model declarations go through _declared_model_ids() so
models: [{id: ...}] rows keep working
- gateway model-switch handler moved to gateway/slash_commands.py since
the PR branched — re-applied the display-form edits there (both the
legacy picker closure and the current typed path)
- regression tests: same-endpoint fold, api_mode separation,
header-routed separation, list-of-dict models, RID display stripping
