feat: Introduce activity schema headline binding for improved metrics handling

- Added a new function `activitySchemaHeadlineBinding` to streamline the binding of profile parameters to their corresponding headline columns, enhancing clarity in the metrics display logic.
- Refactored the `SessionMetricsFields` component to utilize the new binding function, simplifying the filtering of schema entries and improving maintainability.
- Updated the logic in `ActivityPage` to leverage the binding function for determining the appropriate column for metrics, ensuring consistent data handling across the application.

backend/scripts/inspect_activity_eav.py

@@ -0,0 +1,179 @@
+"""
+Diagnose: Was liegt in activity_session_metrics (EAV) vs. activity_log?
+
+Ausführung (mit gesetzten DB_*-Variablen wie die App, z. B. aus .env):
+
+  cd backend
+  python scripts/inspect_activity_eav.py
+
+Lokal ohne Docker-Hostname: z. B. ``set DB_HOST=127.0.0.1`` (Windows) / ``export DB_HOST=127.0.0.1``,
+Port/User/Pass wie in der laufenden Postgres-Instanz.
+
+Im Backend-Container (Compose-Service meist ``backend``, Arbeitsverzeichnis ``/app``):
+
+  docker compose exec backend python /app/scripts/inspect_activity_eav.py
+
+Optional:
+  python scripts/inspect_activity_eav.py --limit 30
+  python scripts/inspect_activity_eav.py --profile <uuid>
+  python scripts/inspect_activity_eav.py --activity <activity_log uuid>
+
+Keine Schreibzugriffe — nur SELECT.
+"""
+from __future__ import annotations
+
+import argparse
+import os
+import sys
+
+# backend/ als Import-Root
+_BACKEND_ROOT = os.path.abspath(os.path.join(os.path.dirname(__file__), ".."))
+if _BACKEND_ROOT not in sys.path:
+    sys.path.insert(0, _BACKEND_ROOT)
+
+
+def _val_row(r: dict) -> str | None:
+    dt = r.get("data_type")
+    if dt == "integer":
+        v = r.get("value_int")
+        return str(v) if v is not None else None
+    if dt == "float":
+        v = r.get("value_num")
+        return str(v) if v is not None else None
+    if dt == "string":
+        v = r.get("value_text")
+        return repr(v) if v is not None else None
+    if dt == "boolean":
+        v = r.get("value_bool")
+        return str(v) if v is not None else None
+    return None
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser(description="EAV activity_session_metrics inspizieren")
+    parser.add_argument("--limit", type=int, default=40, help="Zeilen Report A/B")
+    parser.add_argument("--profile", type=str, default=None, help="profile_id filtern")
+    parser.add_argument("--activity", type=str, default=None, help="activity_log.id (einzelne Session)")
+    args = parser.parse_args()
+
+    from db import get_db, get_cursor
+
+    if args.activity:
+        with get_db() as conn:
+            with get_cursor(conn) as cur:
+                cur.execute(
+                    """
+                    SELECT al.id, al.profile_id, al.date, al.start_time, al.source,
+                           al.training_category, al.training_type_id, al.activity_type,
+                           al.duration_min, al.kcal_active, al.hr_avg, al.hr_max, al.distance_km
+                    FROM activity_log al
+                    WHERE al.id = %s::uuid
+                    """,
+                    (args.activity,),
+                )
+                h = cur.fetchone()
+                if not h:
+                    print("activity_log: keine Zeile für diese id")
+                    return
+                print("=== activity_log (Kopfzeile) ===")
+                for k, v in dict(h).items():
+                    print(f"  {k}: {v}")
+
+                cur.execute(
+                    """
+                    SELECT m.id AS metric_id, tp.key, tp.data_type, tp.source_field,
+                           m.value_num, m.value_int, m.value_text, m.value_bool, m.updated_at
+                    FROM activity_session_metrics m
+                    JOIN training_parameters tp ON tp.id = m.training_parameter_id
+                    WHERE m.activity_log_id = %s::uuid
+                    ORDER BY tp.key
+                    """,
+                    (args.activity,),
+                )
+                rows = cur.fetchall()
+                print(f"\n=== activity_session_metrics ({len(rows)} Zeilen) ===")
+                for r in rows:
+                    d = dict(r)
+                    print(
+                        f"  {d['key']} ({d['data_type']}) "
+                        f"value={_val_row(d)!r} source_field={d.get('source_field')!r} "
+                        f"updated_at={d.get('updated_at')}"
+                    )
+                if not rows:
+                    print("  (keine EAV-Zeilen)")
+        return
+
+    prof_filter = ""
+    if args.profile:
+        prof_filter = " AND al.profile_id = %s::uuid "
+    params_a: tuple = (args.profile, args.limit) if args.profile else (args.limit,)
+    params_b: tuple = (args.profile, args.limit) if args.profile else (args.limit,)
+
+    q_recent_eav = f"""
+        SELECT
+            al.id AS activity_id,
+            al.profile_id,
+            al.date,
+            al.start_time,
+            al.source,
+            al.training_type_id,
+            al.training_category,
+            tp.key AS parameter_key,
+            tp.data_type,
+            tp.source_field AS tp_source_field,
+            m.value_num,
+            m.value_int,
+            m.value_text,
+            m.value_bool,
+            m.updated_at
+        FROM activity_session_metrics m
+        JOIN activity_log al ON al.id = m.activity_log_id
+        JOIN training_parameters tp ON tp.id = m.training_parameter_id
+        WHERE 1=1 {prof_filter}
+        ORDER BY m.updated_at DESC NULLS LAST, al.date DESC, al.start_time DESC
+        LIMIT %s
+    """
+
+    q_csv_no_eav = f"""
+        SELECT
+            al.id AS activity_id,
+            al.profile_id,
+            al.date,
+            al.start_time,
+            al.source,
+            al.training_type_id,
+            al.training_category,
+            (SELECT COUNT(*) FROM activity_session_metrics m WHERE m.activity_log_id = al.id) AS eav_count
+        FROM activity_log al
+        WHERE al.source = 'csv' {prof_filter}
+        ORDER BY al.date DESC, al.start_time DESC
+        LIMIT %s
+    """
+
+    with get_db() as conn:
+        with get_cursor(conn) as cur:
+            print("=== A) Neueste EAV-Zeilen (join activity_log + training_parameters) ===\n")
+            cur.execute(q_recent_eav, params_a)
+            for r in cur.fetchall():
+                d = dict(r)
+                v = _val_row(d)
+                print(
+                    f"{d['date']} {d['start_time']} | {d['activity_id']} | src={d['source']!r} | "
+                    f"type={d['training_type_id']} cat={d['training_category']!r} | "
+                    f"{d['parameter_key']}={v!r} (tp.source_field={d.get('tp_source_field')!r})"
+                )
+
+            print("\n=== B) Neueste CSV-importierte Sessions: EAV-Anzahl pro Zeile ===\n")
+            cur.execute(q_csv_no_eav, params_b)
+            for r in cur.fetchall():
+                d = dict(r)
+                print(
+                    f"{d['date']} {d['start_time']} | {d['activity_id']} | "
+                    f"type={d['training_type_id']} | eav_count={d['eav_count']}"
+                )
+
+    print("\nFertig. Für eine Session im Detail: --activity <uuid>")
+
+
+if __name__ == "__main__":
+    main()

frontend/src/pages/ActivityPage.jsx

@@ -106,6 +106,23 @@ const ENTRY_FORM_ACTIVITY_LOG_COLUMNS = new Set([
   'notes',
 ])
 
+/**
+ * Bindung Profilparameter ↔ Kopfzeile: Entweder source_field zeigt auf eine Kopfspalte,
+ * oder der Parameter-key ist selbst eine Kopfspalte (häufig nach Migration / ohne source_field).
+ * @returns {{ headlineCol: string, parameterKey: string } | null}
+ */
+function activitySchemaHeadlineBinding(s) {
+  if (!s || !s.key) return null
+  const sf = s.source_field != null ? String(s.source_field).trim() : ''
+  if (sf && ENTRY_FORM_ACTIVITY_LOG_COLUMNS.has(sf)) {
+    return { headlineCol: sf, parameterKey: s.key }
+  }
+  if (ENTRY_FORM_ACTIVITY_LOG_COLUMNS.has(s.key)) {
+    return { headlineCol: s.key, parameterKey: s.key }
+  }
+  return null
+}
+
 function empty() {
   return {
     date: dayjs().format('YYYY-MM-DD'),
@@ -157,18 +174,9 @@ function buildMetricsPayload(schema, draft) {
 function SessionMetricsFields({ schema, values, setValues, metrics }) {
   const schemaList = Array.isArray(schema) ? schema : []
   const headlineDuplicateKeys = new Set(
-    schemaList
-      .filter((s) => {
-        const sf = s.source_field != null ? String(s.source_field).trim() : ''
-        return sf && ENTRY_FORM_ACTIVITY_LOG_COLUMNS.has(sf)
-      })
-      .map((s) => s.key),
+    schemaList.filter((s) => activitySchemaHeadlineBinding(s) != null).map((s) => s.key),
   )
-  const schemaForDisplay = schemaList.filter((s) => {
-    const sf = s.source_field != null ? String(s.source_field).trim() : ''
-    if (!sf) return true
-    return !ENTRY_FORM_ACTIVITY_LOG_COLUMNS.has(sf)
-  })
+  const schemaForDisplay = schemaList.filter((s) => activitySchemaHeadlineBinding(s) == null)
   const metricRows = Array.isArray(metrics) ? metrics : []
   const schemaKeys = new Set(schemaForDisplay.map((s) => s.key))
   const orphanMetrics = metricRows.filter(
@@ -655,10 +663,10 @@ export default function ActivityPage() {
       if (sessionDetail?.schema?.length > 0) {
         const draftForMetrics = { ...metricDraft }
         for (const s of sessionDetail.schema) {
-          const sf = s.source_field != null ? String(s.source_field).trim() : ''
-          if (!sf || !ENTRY_FORM_ACTIVITY_LOG_COLUMNS.has(sf)) continue
-          if (!(s.key in draftForMetrics)) continue
-          const rawCol = payload[sf] !== undefined ? payload[sf] : editing?.[sf]
+          const bind = activitySchemaHeadlineBinding(s)
+          if (!bind || !(s.key in draftForMetrics)) continue
+          const rawCol =
+            payload[bind.headlineCol] !== undefined ? payload[bind.headlineCol] : editing?.[bind.headlineCol]
           if (rawCol === undefined) continue
           if (s.data_type === 'boolean') {
             draftForMetrics[s.key] = !!rawCol