OWNERSHIP: residency classification (Bestand vs external ancestors)

Per hive/agents/god/OWNERSHIP-residency.md (Julian): "Clan kleine Chaoten"
is the wife's own Zucht. Classify each animal:
 (a) RESIDENT if zuchtCanon contains 'kleinechaote' (separator/declension-
     insensitive: "v.d. Kleinen Chaoten", "Clan-Kleine-Chaoten", …); OR
 (b) PARENT EXCEPTION — a parent of a Clan offspring is resident even if its
     own Zuchtname is foreign (you can only breed a Clan litter if the parents
     were in your care). Runs AFTER the parentRefs→litter linking.
Otherwise EXTERNAL (pedigree ancestor, not living stock — kept, not deleted).

Stored as a dedicated Gerbil.IsResident bool (distinct from Status/Abgabe —
origin/identity, not current location), defaulting true (own stock unless
marked external; DB HasDefaultValue(true)). Additive migration
AddGerbilResidency; has-pending-model-changes clean. Round-trips in
GerbilDto/GerbilInput and is Gridify-filterable (isResident==true) so Kevin
can build a "nur Bestand" filter. ImportService computes it at (re-)import
and refreshes existing rows on the idempotent sweep. ResidencySummary added
to the import report.

Projected on real data: 306 loadable → 227 resident (188 rule a, +39 via
parent exception), 79 external ancestors.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

GerbilManagerWebAPI/Import/ImportService.cs

@@ -192,6 +192,17 @@ namespace GerbilManagerWebAPI.Import
                 parentLinksAdded++;
             }
 
+            // litter id -> (father, mother) gids, across synthesized + Wurfchronik (by name) litters.
+            // Used by the residency rule (b) below; augmented with existing DB litters under execute.
+            var litterParents = new Dictionary<Guid, (Guid? F, Guid? M)>();
+            foreach (var sl in synthLitters.Values)
+                litterParents[sl.Id] = (sl.Father, sl.Mother);
+            foreach (var sl in litters)
+                if (litterIdMap.TryGetValue(sl.Id, out var lid))
+                    litterParents[lid] = (
+                        createdAnimalByName.TryGetValue(Normalize(StripZucht(sl.SireName)), out var fid) ? fid : (Guid?)null,
+                        createdAnimalByName.TryGetValue(Normalize(StripZucht(sl.DamName)), out var mid) ? mid : (Guid?)null);
+
             // PASS 2: write (litters synthesized first so offspring FK resolves), then animals + photos.
             if (execute)
             {
@@ -200,7 +211,10 @@ namespace GerbilManagerWebAPI.Import
                     .Select(l => new { l.Id, l.FatherId, l.MotherId, l.Date }).ToListAsync();
                 var litterByParentsDate = new Dictionary<string, Guid>();
                 foreach (var l in existingLitterRows)
+                {
                     litterByParentsDate[$"{l.FatherId}|{l.MotherId}|{l.Date:yyyy-MM-dd}"] = l.Id;
+                    litterParents[l.Id] = (l.FatherId, l.MotherId);
+                }
 
                 foreach (var sl in synthLitters.Values.ToList())
                 {
@@ -226,11 +240,31 @@ namespace GerbilManagerWebAPI.Import
                 await _db.SaveChangesAsync();
             }
 
+            // OWNERSHIP/RESIDENCY (runs AFTER litter links exist): (a) Zuchtname matches the Clan
+            // kennel (zuchtCanon contains 'kleinechaote'); (b) parent of a Clan offspring, even if
+            // the parent's own Zuchtname is foreign. See hive/agents/god/OWNERSHIP-residency.md.
+            static bool ClanCanon(string? zc) =>
+                (zc ?? "").Contains("kleinechaote", StringComparison.OrdinalIgnoreCase);
+            var resident = new HashSet<Guid>();
+            foreach (var p in plan) if (ClanCanon(p.A.ZuchtCanon)) resident.Add(p.Gid);   // (a)
+            int residentByA = resident.Count, flippedByParentRule = 0;
+            foreach (var p in plan)
+            {
+                if (!ClanCanon(p.A.ZuchtCanon)) continue;
+                var litId = p.WurfLitterId ?? (synthLitterForGid.TryGetValue(p.Gid, out var s) ? s : (Guid?)null);
+                if (litId is null || !litterParents.TryGetValue(litId.Value, out var par)) continue;
+                if (par.F is Guid gf && resident.Add(gf)) flippedByParentRule++;   // (b)
+                if (par.M is Guid gm && resident.Add(gm)) flippedByParentRule++;
+            }
+            int residentTotal = plan.Count(p => resident.Contains(p.Gid));
+            int externalTotal = plan.Count - residentTotal;
+
             foreach (var p in plan)
             {
                 Guid? litterId = p.WurfLitterId
                     ?? (synthLitterForGid.TryGetValue(p.Gid, out var slid) ? slid : (Guid?)null);
                 if (litterId is not null) linked++;
+                bool isResident = resident.Contains(p.Gid);
 
                 if (p.ColorVarietyId is null) fbUnmatched++; else fbMatched++;
 
@@ -242,11 +276,15 @@ namespace GerbilManagerWebAPI.Import
                 if (p.Exists)
                 {
                     animalsExisting++;
-                    // re-link an existing animal that just became linkable (sweep idempotency).
-                    if (execute && p.CurrentLitterId is null && litterId is not null)
+                    // sweep idempotency: re-link a now-linkable animal + refresh its residency.
+                    if (execute)
                     {
                         var row = await _db.Gerbils.FirstOrDefaultAsync(g => g.Id == p.Gid);
-                        if (row is not null) row.LitterId = litterId;
+                        if (row is not null)
+                        {
+                            if (p.CurrentLitterId is null && litterId is not null) row.LitterId = litterId;
+                            row.IsResident = isResident;
+                        }
                     }
                     continue;
                 }
@@ -266,6 +304,7 @@ namespace GerbilManagerWebAPI.Import
                         ColorVarietyId = p.ColorVarietyId,
                         Genotype = ComposeGenotype(p.A.Genotype),
                         IsDeaf = p.A.Deaf,
+                        IsResident = isResident,
                         ImportSource = ImportSourceTag,
                         ExternalRef = p.A.Id,
                         OriginBreeder = string.IsNullOrWhiteSpace(p.A.Zucht) ? null : p.A.Zucht.Trim(),
@@ -328,6 +367,7 @@ namespace GerbilManagerWebAPI.Import
             notes.Add("Quarantäne (kein Import): Konflikte + Stubs ohne Geburtsdatum + unsichere Wurf-Zuordnungen — warten auf die Prüfung durch die Züchterin.");
             if (parentLinksAdded > 0)
                 notes.Add($"Stammbaum-Diagramm: {parentLinksAdded} Tiere über Eltern-Verknüpfung einem (abgeleiteten) Wurf zugeordnet ({derivedLitters} abgeleitete Würfe).");
+            notes.Add($"Bestand/Herkunft: {residentTotal} im Bestand (Clan Kleine Chaoten), {externalTotal} externe Ahnen ({flippedByParentRule} davon über die Eltern-Regel als Bestand erkannt).");
             if (!execute) notes.Add("DRY-RUN: nichts gespeichert. /import/execute lädt die konfliktfreien Daten.");
 
             return new ImportReport(
@@ -339,7 +379,8 @@ namespace GerbilManagerWebAPI.Import
                     parentLinksAdded),
                 Photos: new PhotoSummary(photosAttached, photosMissing),
                 Samples: samples,
-                Notes: notes);
+                Notes: notes,
+                Residency: new ResidencySummary(residentTotal, externalTotal, flippedByParentRule));
         }
 
         private T? Load<T>(string file)