feat(backend): patient garden — deterministic growth from activities

GET /api/v1/me/{token}/garden computes the garden on the fly from taken doses,
check-ins/diary and finished questionnaires (no new table). Rules and texts in
config/garden.yaml: per-day caps, points only add up, answers never count.

Refs #118

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

app/api/patient_web.py

@@ -43,6 +43,7 @@ from app.db.intake import QuestionnaireRecord
 from app.db.session import get_clinical_session, get_identity_session
 from app.integrations.emias_mock import CODE_MAX_LEN, EmiasMock
 from app.services import anonymous_care
+from app.services.garden import Garden, garden_for
 
 log = logging.getLogger(__name__)
 
@@ -374,6 +375,18 @@ async def my_today(token: str) -> TodayOut:
     )
 
 
+@router.get("/me/{token}/garden", response_model=Garden)
+async def my_garden(token: str) -> Garden:
+    """The patient's garden (#118): grows from medication marks, check-ins/diary and finished questionnaires.
+
+    Never shrinks and never depends on answers. Seen only by the patient — not on the dashboard, not in summaries.
+    """
+    async with get_clinical_session() as s:
+        if await repo.get_profile(s, token) is None:
+            raise HTTPException(404, "patient not found")
+        return await garden_for(s, token)
+
+
 class ResultFinding(BaseModel):
     code: str
     title: str