feat: circ_summary with best-of-each strategy and age annotations

- Each circumference point shows most recent value (even from different dates)
- Age annotations: heute, gestern, vor X Tagen/Wochen/Monaten
- Gives AI better context about measurement freshness
- Example: 'Brust 105cm (heute), Nacken 38cm (vor 2 Wochen)'

backend/placeholder_resolver.py

@@ -123,33 +123,62 @@ def get_caliper_summary(profile_id: str) -> str:
 
 
 def get_circ_summary(profile_id: str) -> str:
-    """Get latest circumference measurements summary."""
+    """Get latest circumference measurements summary with age annotations.
+
+    For each measurement point, fetches the most recent value (even if from different dates).
+    Annotates each value with measurement age for AI context.
+    """
     with get_db() as conn:
         cur = get_cursor(conn)
+
+        # Define all circumference points with their labels
+        fields = [
+            ('c_neck', 'Nacken'),
+            ('c_chest', 'Brust'),
+            ('c_waist', 'Taille'),
+            ('c_belly', 'Bauch'),
+            ('c_hip', 'Hüfte'),
+            ('c_thigh', 'Oberschenkel'),
+            ('c_calf', 'Wade'),
+            ('c_arm', 'Arm')
+        ]
+
+        parts = []
+        today = datetime.now().date()
+
+        # Get latest value for each field individually
+        for field_name, label in fields:
             cur.execute(
-            """SELECT c_neck, c_chest, c_waist, c_belly, c_hip, c_thigh, c_calf, c_arm, date
+                f"""SELECT {field_name}, date,
+                           CURRENT_DATE - date AS age_days
                     FROM circumference_log
-               WHERE profile_id=%s
+                    WHERE profile_id=%s AND {field_name} IS NOT NULL
                     ORDER BY date DESC LIMIT 1""",
                 (profile_id,)
             )
             row = r2d(cur.fetchone()) if cur.rowcount > 0 else None
 
-        if not row:
-            return "keine Umfangsmessungen"
+            if row:
+                value = row[field_name]
+                age_days = row['age_days']
 
-        # Check all 8 circumference points
-        parts = []
-        if row.get('c_neck'): parts.append(f"Nacken {row['c_neck']:.1f}cm")
-        if row.get('c_chest'): parts.append(f"Brust {row['c_chest']:.1f}cm")
-        if row.get('c_waist'): parts.append(f"Taille {row['c_waist']:.1f}cm")
-        if row.get('c_belly'): parts.append(f"Bauch {row['c_belly']:.1f}cm")
-        if row.get('c_hip'): parts.append(f"Hüfte {row['c_hip']:.1f}cm")
-        if row.get('c_thigh'): parts.append(f"Oberschenkel {row['c_thigh']:.1f}cm")
-        if row.get('c_calf'): parts.append(f"Wade {row['c_calf']:.1f}cm")
-        if row.get('c_arm'): parts.append(f"Arm {row['c_arm']:.1f}cm")
+                # Format age annotation
+                if age_days == 0:
+                    age_str = "heute"
+                elif age_days == 1:
+                    age_str = "gestern"
+                elif age_days <= 7:
+                    age_str = f"vor {age_days} Tagen"
+                elif age_days <= 30:
+                    weeks = age_days // 7
+                    age_str = f"vor {weeks} Woche{'n' if weeks > 1 else ''}"
+                else:
+                    months = age_days // 30
+                    age_str = f"vor {months} Monat{'en' if months > 1 else ''}"
 
-        return f"{', '.join(parts)} ({row['date']})" if parts else "keine Daten"
+                parts.append(f"{label} {value:.1f}cm ({age_str})")
+
+        return ', '.join(parts) if parts else "keine Umfangsmessungen"
 
 
 def get_goal_weight(profile_id: str) -> str: