fix: Prevent manual progress entries for automatic goals

**Backend Safeguards:**
- get_goals_grouped: Added source_table, source_column, direction to SELECT
- create_goal_progress: Check source_table before allowing manual entry
- Returns HTTP 400 if user tries to log progress for automatic goals (weight, activity, etc.)

**Prevents:**
- Data confusion: Manual entries in goal_progress_log for weight/activity/etc.
- Dual tracking: Same data in multiple tables
- User error: Wrong data entry location

**Result:**
- Frontend filter (!goal.source_table) now works correctly
- CustomGoalsPage shows ONLY custom goals (flexibility, strength, etc.)
- Clear error message if manual entry attempted via API

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

backend/routers/goals.py

@@ -561,15 +561,25 @@ def create_goal_progress(goal_id: str, data: GoalProgressCreate, session: dict =
     with get_db() as conn:
         cur = get_cursor(conn)
 
-        # Verify ownership
-        cur.execute(
-            "SELECT id, unit FROM goals WHERE id = %s AND profile_id = %s",
-            (goal_id, pid)
-        )
+        # Verify ownership and check if manual entry is allowed
+        cur.execute("""
+            SELECT g.id, g.unit, gt.source_table
+            FROM goals g
+            LEFT JOIN goal_type_definitions gt ON g.goal_type = gt.type_key
+            WHERE g.id = %s AND g.profile_id = %s
+        """, (goal_id, pid))
         goal = cur.fetchone()
         if not goal:
             raise HTTPException(status_code=404, detail="Ziel nicht gefunden")
 
+        # Prevent manual entries for goals with automatic data sources
+        if goal['source_table']:
+            raise HTTPException(
+                status_code=400,
+                detail=f"Manuelle Einträge nicht erlaubt für automatisch erfasste Ziele. "
+                       f"Bitte nutze die entsprechende Erfassungsseite (z.B. Gewicht, Aktivität)."
+            )
+
         # Insert progress entry
         try:
             cur.execute("""
@@ -660,7 +670,8 @@ def get_goals_grouped(session: dict = Depends(require_auth)):
                 g.unit, g.target_date, g.status, g.is_primary, g.category, g.priority,
                 g.name, g.description, g.progress_pct, g.on_track, g.projection_date,
                 g.created_at, g.updated_at,
-                gt.label_de, gt.icon, gt.category as type_category
+                gt.label_de, gt.icon, gt.category as type_category,
+                gt.source_table, gt.source_column, gt.direction
             FROM goals g
             LEFT JOIN goal_type_definitions gt ON g.goal_type = gt.type_key
             WHERE g.profile_id = %s