refactor(skin): replace trend with texture field on SkinConditionSnapshot

Remove the derived `trend` field (better computed from history by the MCP
agent) and add `texture: smooth|rough|flaky|bumpy` which LLM can reliably
assess from photos. Updates model, API, system prompt, tests, and frontend.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/innercontext/api/skincare.py

@@ -20,7 +20,7 @@ from innercontext.models.enums import (
     BarrierState,
     OverallSkinState,
     SkinConcern,
-    SkinTrend,
+    SkinTexture,
     SkinType,
 )
 
@@ -39,8 +39,8 @@ class SnapshotCreate(SkinConditionSnapshotBase):
 class SnapshotUpdate(SQLModel):
     snapshot_date: Optional[date] = None
     overall_state: Optional[OverallSkinState] = None
-    trend: Optional[SkinTrend] = None
     skin_type: Optional[SkinType] = None
+    texture: Optional[SkinTexture] = None
 
     hydration_level: Optional[int] = None
     sebum_tzone: Optional[int] = None
@@ -57,8 +57,8 @@ class SnapshotUpdate(SQLModel):
 
 class SkinPhotoAnalysisResponse(SQLModel):
     overall_state: Optional[OverallSkinState] = None
-    trend: Optional[SkinTrend] = None
     skin_type: Optional[SkinType] = None
+    texture: Optional[SkinTexture] = None
     hydration_level: Optional[int] = None
     sebum_tzone: Optional[int] = None
     sebum_cheeks: Optional[int] = None
@@ -85,14 +85,13 @@ RULES:
 - Omit any field you cannot confidently determine from the photos. Do not guess.
 - All enum values must exactly match the allowed strings listed below.
 - Numeric metrics use a 1–5 scale (1 = minimal, 5 = maximal).
-- For trends: only populate if you have strong visual cues; otherwise omit.
 - risks and priorities: short English phrases, max 10 words each.
 - notes: 2–4 sentence paragraph describing key observations.
 
 ENUM VALUES:
 overall_state: "excellent" | "good" | "fair" | "poor"
-trend: "improving" | "stable" | "worsening" | "fluctuating"
 skin_type: "dry" | "oily" | "combination" | "sensitive" | "normal" | "acne_prone"
+texture: "smooth" | "rough" | "flaky" | "bumpy"
 barrier_state: "intact" | "mildly_compromised" | "compromised"
 active_concerns: "acne" | "rosacea" | "hyperpigmentation" | "aging" | "dehydration" |
   "redness" | "damaged_barrier" | "pore_visibility" | "uneven_texture" | "sebum_excess"
@@ -104,7 +103,7 @@ sebum_cheeks: 1=very dry cheeks → 5=very oily cheeks
 sensitivity_level: 1=no visible signs → 5=severe redness/reactivity
 
 OUTPUT (all fields optional):
-{"overall_state":…, "trend":…, "skin_type":…, "hydration_level":…,
+{"overall_state":…, "skin_type":…, "texture":…, "hydration_level":…,
  "sebum_tzone":…, "sebum_cheeks":…, "sensitivity_level":…,
  "barrier_state":…, "active_concerns":[…], "risks":[…], "priorities":[…], "notes":…}
 """

backend/innercontext/models/__init__.py

@@ -15,7 +15,7 @@ from .enums import (
     ResultFlag,
     RoutineRole,
     SkinConcern,
-    SkinTrend,
+    SkinTexture,
     SkinType,
     StrengthLevel,
     TextureType,
@@ -59,7 +59,7 @@ __all__ = [
     "ResultFlag",
     "RoutineRole",
     "SkinConcern",
-    "SkinTrend",
+    "SkinTexture",
     "SkinType",
     "StrengthLevel",
     "TextureType",

backend/innercontext/models/enums.py

@@ -186,11 +186,11 @@ class OverallSkinState(str, Enum):
     POOR = "poor"
 
 
-class SkinTrend(str, Enum):
-    IMPROVING = "improving"
-    STABLE = "stable"
-    WORSENING = "worsening"
-    FLUCTUATING = "fluctuating"
+class SkinTexture(str, Enum):
+    SMOOTH = "smooth"
+    ROUGH = "rough"
+    FLAKY = "flaky"
+    BUMPY = "bumpy"
 
 
 class BarrierState(str, Enum):

backend/innercontext/models/skincare.py

@@ -9,7 +9,7 @@ from sqlmodel import Field, SQLModel
 
 from .base import utc_now
 from .domain import Domain
-from .enums import BarrierState, OverallSkinState, SkinConcern, SkinTrend, SkinType
+from .enums import BarrierState, OverallSkinState, SkinConcern, SkinTexture, SkinType
 
 # ---------------------------------------------------------------------------
 # Base model (pure Python types, no sa_column, no id/created_at)
@@ -20,8 +20,8 @@ class SkinConditionSnapshotBase(SQLModel):
     snapshot_date: date
 
     overall_state: OverallSkinState | None = None
-    trend: SkinTrend | None = None
     skin_type: SkinType | None = None
+    texture: SkinTexture | None = None
 
     # Metryki wizualne (1 = minimalne, 5 = maksymalne nasilenie)
     hydration_level: int | None = Field(default=None, ge=1, le=5)

backend/tests/test_skincare.py

@@ -16,8 +16,8 @@ def test_create_snapshot_full(client):
         json={
             "snapshot_date": "2026-02-20",
             "overall_state": "good",
-            "trend": "improving",
             "skin_type": "combination",
+            "texture": "rough",
             "hydration_level": 3,
             "sebum_tzone": 4,
             "sebum_cheeks": 2,
@@ -32,7 +32,7 @@ def test_create_snapshot_full(client):
     assert r.status_code == 201
     data = r.json()
     assert data["overall_state"] == "good"
-    assert data["trend"] == "improving"
+    assert data["texture"] == "rough"
     assert "acne" in data["active_concerns"]
     assert data["hydration_level"] == 3