feat: Fehler-melden + Datenherkunft auf Kontakte & Würfe erweitern

- Kontakt-Detailseite: „Fehler melden"- und „Datenherkunft"-Button.
- Wurf-Ansicht: „Datenherkunft"-Button (Feedback war bereits vorhanden).
- Feedback-Entity um loses, nullable ContactId erweitert (kein FK → übersteht
  Ingest-Wipe); Migration AddFeedbackContactId.
- Contact.Provenance + Litter.Provenance (nullable text); Migration
  AddContactLitterProvenance; im Ingest gemappt und in den DTOs zurückgegeben.
- Import: build_entity_provenance() generalisiert; Kontakte (sourceFiles,
  Züchter/Abnehmer-Hinweise) und Würfe (Wurfchronik vs. Diagramm-rekonstruiert,
  Geschwister-Merge) erhalten Herkunftsdaten in resolved_import.json.
- Frontend: ProvenanceDialog generalisiert (EntityProvenance + entityLabel).

Tests erweitert (Ingest-Round-trip Kontakt/Wurf, contact-scoped Feedback
übersteht Wipe). dotnet(212)/vitest(129)/playwright(36)/tsc/eslint grün.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tools/import/merge_and_resolve.py

@@ -22,6 +22,30 @@ def generate_guid(key_str):
     """Generate a stable UUID string based on a key."""
     return str(uuid.uuid5(uuid.NAMESPACE_DNS, key_str))
 
+def build_entity_provenance(source_files, merged_record_count, notes=None,
+                            from_wurfchronik=None, extra=None):
+    """Generic data-provenance JSON builder shared by gerbils, contacts and
+    litters. Mirrors the GerbilProvenance frontend contract:
+      { sourceFiles, mergedRecordCount, fromWurfchronik, notes, ... }
+    `source_files` is any iterable of filenames; `from_wurfchronik` is auto-
+    derived from the filenames when left as None. `extra` may carry entity-
+    specific keys (e.g. parentMethod/parentConfidence for gerbils). Returns a
+    JSON string (stored on the nullable Provenance text column)."""
+    files = sorted({f for f in source_files if f})
+    if from_wurfchronik is None:
+        from_wurfchronik = any("wurfchronik" in f.lower() for f in files)
+    prov = {
+        "sourceFiles": files,
+        "mergedRecordCount": merged_record_count,
+        "fromWurfchronik": bool(from_wurfchronik),
+        "notes": list(notes or []),
+    }
+    if extra:
+        for k, v in extra.items():
+            if v is not None:
+                prov[k] = v
+    return json.dumps(prov, ensure_ascii=False)
+
 def to_valid_guid(val):
     if not val:
         return None
@@ -1101,6 +1125,7 @@ def main():
 
         norm_name = normalize_name(canon_name)
 
+        rc_file = rc.get("_filename")
         if norm_name not in contact_by_norm_name:
             global_guid = generate_guid(f"contact-{norm_name}")
             contact_by_norm_name[norm_name] = {
@@ -1109,7 +1134,10 @@ def main():
                 "Email": rc.get("Email") or rc.get("email"),
                 "Phone": rc.get("Phone") or rc.get("phone"),
                 "Address": rc.get("Address") or rc.get("address"),
-                "Notes": rc.get("Notes") or rc.get("notes") or rc.get("Note") or rc.get("note")
+                "Notes": rc.get("Notes") or rc.get("notes") or rc.get("Note") or rc.get("note"),
+                # Provenance accumulators (consumed below, stripped from helper keys).
+                "_source_files": set([rc_file]) if rc_file else set(),
+                "_merged_count": 1,
             }
         else:
             gc = contact_by_norm_name[norm_name]
@@ -1121,6 +1149,9 @@ def main():
                 gc["Address"] = rc.get("Address") or rc.get("address")
             if not gc["Notes"] and (rc.get("Notes") or rc.get("notes") or rc.get("Note") or rc.get("note")):
                 gc["Notes"] = rc.get("Notes") or rc.get("notes") or rc.get("Note") or rc.get("note")
+            if rc_file:
+                gc["_source_files"].add(rc_file)
+            gc["_merged_count"] += 1
 
         if scoped_id:
             contact_id_map[scoped_id] = contact_by_norm_name[norm_name]["Id"]
@@ -1189,7 +1220,13 @@ def main():
             "LitterLetter": rl.get("LitterLetter") or rl.get("litterLetter"),
             "_father_name": father_name,
             "_mother_name": mother_name,
-            "_filename": filename
+            "_filename": filename,
+            # Provenance accumulators (canonical absorbs these during dedup below).
+            "_source_files": set([filename]) if filename else set(),
+            "_merged_count": 1,
+            # Virtual litters are reconstructed from a Stammbaum chart, not the
+            # Wurfchronik — flagged on the raw record's _filename == "Stammbaum".
+            "_virtual": filename == "Stammbaum",
         }
         resolved_litters.append(l_record)
         litter_by_scoped_id[new_guid] = l_record
@@ -1236,6 +1273,10 @@ def main():
                 litter_dedup_canonical[l["Id"]] = canonical["Id"]
                 if l is not canonical:
                     litter_id_map[l["Id"]] = canonical["Id"]
+                    canonical["_source_files"] |= l.get("_source_files", set())
+                    canonical["_merged_count"] += l.get("_merged_count", 1)
+                    if not l.get("_virtual"):
+                        canonical["_virtual"] = False
 
             deduped_litters.append(canonical)
             if len(sub) > 1:
@@ -1742,17 +1783,13 @@ def main():
                 if n and n not in notes:
                     notes.append(n)
 
-        prov = {
-            "sourceFiles": sorted(source_files),
-            "mergedRecordCount": merged_count,
-            "fromWurfchronik": from_wurfchronik,
-            "notes": notes,
-        }
-        if parent_method:
-            prov["parentMethod"] = parent_method
-        if parent_confidence:
-            prov["parentConfidence"] = parent_confidence
-        return json.dumps(prov, ensure_ascii=False)
+        return build_entity_provenance(
+            source_files,
+            merged_count,
+            notes=notes,
+            from_wurfchronik=from_wurfchronik,
+            extra={"parentMethod": parent_method, "parentConfidence": parent_confidence},
+        )
 
     # Group gerbils by name to perform deduplication
     gerbil_groups = {}
@@ -2167,6 +2204,11 @@ def main():
             canonical = max(sub, key=lambda l: len(gerbil_by_litter.get(l["Id"], [])))
             for l in sub:
                 litter_remap2[l["Id"]] = canonical["Id"]
+                if l is not canonical:
+                    canonical["_source_files"] |= l.get("_source_files", set())
+                    canonical["_merged_count"] += l.get("_merged_count", 1)
+                    if not l.get("_virtual"):
+                        canonical["_virtual"] = False
             deduped2.append(canonical)
             if len(sub) > 1:
                 siblings = [g["Name"] for l in sub for g in gerbil_by_litter.get(l["Id"], []) if l is not canonical]
@@ -2186,6 +2228,29 @@ def main():
     resolved_litters = deduped2
     litter_by_scoped_id = {l["Id"]: l for l in resolved_litters}
 
+    # Datenherkunft for litters: which source files contributed, whether this is
+    # a Wurfchronik litter vs a Stammbaum-reconstructed ("virtual") litter, how
+    # many raw records merged into it, plus human-readable notes. Accumulators
+    # (_source_files/_merged_count/_virtual) were filled during the two dedup
+    # passes above; strip them after use.
+    for l in resolved_litters:
+        l_source_files = l.pop("_source_files", set())
+        l_merged_count = l.pop("_merged_count", 1)
+        is_virtual = l.pop("_virtual", False)
+        l_from_wurfchronik = any("wurfchronik" in str(f).lower() for f in l_source_files)
+        l_notes = []
+        if is_virtual and not l_from_wurfchronik:
+            l_notes.append("aus Stammbaum-Diagramm rekonstruiert")
+        elif l_from_wurfchronik:
+            l_notes.append("aus Wurfchronik")
+        if l_merged_count > 1:
+            l_notes.append(f"aus {l_merged_count} Datensätzen zusammengeführt")
+            l_notes.append("Geschwister-Würfe zusammengeführt")
+        l["Provenance"] = build_entity_provenance(
+            l_source_files, l_merged_count, notes=l_notes,
+            from_wurfchronik=l_from_wurfchronik,
+        )
+
     # Set IsBreeder and IsReceiver flags on contacts
     breeder_ids = {g["OriginContactId"] for g in resolved_gerbils if g.get("OriginContactId")}
     receiver_ids = {g["ReceiverContactId"] for g in resolved_gerbils if g.get("ReceiverContactId")}
@@ -2198,6 +2263,20 @@ def main():
         c["IsBreeder"] = is_breeder
         c["IsReceiver"] = is_receiver
 
+        # Datenherkunft: where this (deduplicated) contact came from, plus the
+        # role we inferred. Accumulator keys (_source_files/_merged_count) were
+        # filled during the contact dedup above; strip them after use.
+        c_source_files = c.pop("_source_files", set())
+        c_merged_count = c.pop("_merged_count", 1)
+        c_notes = []
+        if c_merged_count > 1:
+            c_notes.append(f"aus {c_merged_count} Datensätzen zusammengeführt")
+        if is_breeder:
+            c_notes.append("als Züchter erkannt")
+        if is_receiver:
+            c_notes.append("als Abnehmer erkannt")
+        c["Provenance"] = build_entity_provenance(c_source_files, c_merged_count, notes=c_notes)
+
     # Set and map gerbilPhotos
     resolved_photos = []
     for g in resolved_gerbils: