improvement: treatment UX fully overhauled.

AGENTS.md

@@ -38,6 +38,13 @@ frontend/src/
 
 **Example thin page:** `app/.../treatment/page.tsx` → imports `TreatmentWorkspace` from `components/ui/treatment/`.
 
+**Treatment tab:** Preview and editable form are **separate** until the user clicks **Load into workspace** on a history item. See `.cursor/skills/treatment-workspace/SKILL.md` before changing that flow.
+
+**Treatment lab rules (quick ref):**
+- Lab-dependent details (e.g. prosthesis) **without teeth** can save but **cannot ship** — show `LabShipmentBlockedNotice` + inline banner; toast on dispatch add.
+- **History filters** are client-side only (`treatmentHistoryFilters.ts`): “Not shipped to lab” + single date on already-fetched patient history; includes live current draft when filtering.
+- **Lab case comments** on a detail when sent and lab case tasks are not all `COMPLETED` (`taskProgress` from API).
+
 ## Backend layout
 
 ```
@@ -59,6 +66,7 @@ Errors: `AppException` + `ErrorCode` → frontend `getUserFacingError()`. Never
 | Skill | When to use |
 |-------|-------------|
 | `.cursor/skills/add-feature/` | New tab, API module, or end-to-end feature |
+| `.cursor/skills/treatment-workspace/` | Treatment tab: preview vs form, history, load flow, drafts |
 | `.cursor/skills/frontend-structure/` | Moving components, auditing folder layout |
 | `.cursor/skills/api-errors/` | New backend errors + frontend translations |