{# P4-T13 / P4-T19 — LLM model create + edit form (one template, two modes). Mirrors the admin CRUD form shape (admin_templates.html "add new" card). Inputs (see renderers/admin_llm_models.render_admin_llm_model_edit): * is_edit — True for edit (pre-filled, posts to .../{id}), False for create (empty, posts to /admin/llm-models). * model — column dict (empty {} on create). Prices are Decimal-stringified ("15.000000") or None; dates are ISO strings or None. * stats — ModelUsageStats on edit (read-only impact panel). * pins / is_pinned / pin_summary — archive safeguard (P4-T18): a pinned model's Archive button is disabled with a tooltip listing the pins. * provider_choices — known provider keys for the