v0.51.218 fixed getModelLabel() (the visible chip) for URI-scheme model IDs but
left the same first-segment-slash-strip bug in the matching/dedup paths:
api/config.py _norm_model_id + _get_label_for_model, and static/ui.js
_normalizeConfiguredModelKey. For gpt://folder/model/latest those treat the
path slashes as provider delimiters, mis-normalizing the model-identity key
(the #3360 collision class, for URI ids). Adds a URI-scheme guard to all three
so the scheme is not stripped. Kept v0.51.218's getModelLabel (more thorough
than #3436's variant — it extracts the model name vs returning the whole id);
took #3436's backend + _normalizeConfiguredModelKey halves with backend/frontend
parity tests.
Co-authored-by: b3nw <b3nw@duck.com>
