feat: platform backbone and field capture complete (checkpoint)

Platform backbone (plan 2026-10-13-plattform-rueckgrat), all tasks reviewed:
- webhooks with delivery table, retries and stable delivery id
- calendar handlers; a finished task removes its Outlook event
- tasks, automations, inspections, varroa, treatments, feedings,
  harvests, colonies, wintering, stock and bottling record domain events
  in the same transaction; legacy post-commit calls removed
- row locks through one helper (lockRowForUpdate, lockRowsForShare,
  lockRowsForUpdate)
- job framework with JobRun, cli exit codes, cleanup, task templates,
  daily evaluation, hourly app-backup and the rekey job
- system API and page "Verwaltung > System" with retry
- @nestjs/schedule removed, guard tests against in-process schedulers

Field capture T3 (plan 2026-10-13-t3-erfassung-am-stand), all tasks reviewed:
- inspection photo offline without metadata
- bulk capture for treatments, feedings and varroa (backend + frontend)
- offline stand mode with service worker, offline pages and packs
- offline session, cold start and logout on shared devices

Docs: ARCHITECTURE.md assumptions and sections updated, TASKS.md.
Gates: backend lint, typecheck, 1770 unit, 420 e2e, build, no schema
drift; frontend lint, typecheck, 913 tests, build. Not rolled out.

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

ApiCore-Frontend/src/components/colony-select-field.tsx

@@ -5,25 +5,89 @@ import { fetchColonies } from "@/lib/colonies/api";
 import { colonyOptionLabel } from "@/lib/colonies/labels";
 import { isLivingColony } from "@/lib/colonies/status";
 import type { Colony } from "@/lib/colonies/types";
+import { useCurrentUserId } from "@/lib/auth/auth-context";
+import {
+  OFFLINE_PACKS_QUERY_KEY,
+  listPacks,
+  livingColoniesFromPacks,
+} from "@/lib/apiaries/offline-pack";
+import { isNetworkError } from "@/lib/http/fetch-with-timeout";
 import { Field } from "@/components/form/field";
 import { RecordSelect } from "@/components/form/record-select";
 
 const PLACEHOLDER = "Volk wählen";
 const LOADING_PLACEHOLDER = "Völker werden geladen…";
 const LOAD_ERROR_HINT = "Völker konnten nicht geladen werden – bitte die Seite neu laden.";
+const OFFLINE_PACK_HINT = "Offline: nur Völker der geladenen Stände.";
+const OFFLINE_NOT_LOADED_HINT = "Kein Netz. Lade den Stand vorher mit „Für offline laden“.";
+
+/** What a colony choice needs - a server colony or one from an offline pack. */
+type ColonyChoice = Pick<Colony, "id" | "code" | "status" | "apiaryId">;
 
 function useColonies() {
   return useQuery({ queryKey: ["colonies"], queryFn: () => fetchColonies() });
 }
 
+type ChoicesHint = "load-error" | "offline-not-loaded" | "from-packs";
+
+const HINT_TEXTS: Record<ChoicesHint, string> = {
+  "load-error": LOAD_ERROR_HINT,
+  "offline-not-loaded": OFFLINE_NOT_LOADED_HINT,
+  "from-packs": OFFLINE_PACK_HINT,
+};
+
+interface LivingColonyChoices {
+  colonies: readonly ColonyChoice[] | undefined;
+  isLoading: boolean;
+  hint: ChoicesHint | null;
+}
+
+/**
+ * Every colony from the shared ["colonies"] query - one request for every
+ * colony list on the page. Only when that failed for lack of network (never
+ * on a server refusal) the living colonies of the user's offline packs step
+ * in, from their own query: pack colonies are partial records and never go
+ * into the shared cache.
+ */
+function useLivingColonyChoices(): LivingColonyChoices {
+  const userId = useCurrentUserId();
+  const server = useColonies();
+  // failureReason: offline the retry pauses, so `error` stays unset.
+  const isOffline =
+    server.data === undefined && isNetworkError(server.error ?? server.failureReason);
+  const packs = useQuery({
+    queryKey: [...OFFLINE_PACKS_QUERY_KEY, userId, "living-colonies"],
+    queryFn: async () => livingColoniesFromPacks(await listPacks(userId ?? "")),
+    enabled: isOffline && userId !== null,
+    // Reads this device's storage, never the network.
+    networkMode: "always",
+  });
+
+  if (!isOffline) {
+    return {
+      colonies: server.data,
+      isLoading: server.isLoading,
+      hint: server.isError && server.data === undefined ? "load-error" : null,
+    };
+  }
+  const packColonies = packs.data && packs.data.length > 0 ? packs.data : undefined;
+  let hint: ChoicesHint | null = "offline-not-loaded";
+  if (packColonies) {
+    hint = "from-packs";
+  } else if (packs.isLoading) {
+    hint = null;
+  }
+  return { colonies: packColonies, isLoading: packs.isLoading, hint };
+}
+
 interface ColonyChoicesProps {
   id: string;
   value: string;
   onChange: (colonyId: string) => void;
   /** The colonies on offer; `undefined` while loading. */
-  options: readonly Colony[] | undefined;
+  options: readonly ColonyChoice[] | undefined;
   /** Every known colony, so a chosen one is named even if it is not offered. */
-  colonies: readonly Colony[] | undefined;
+  colonies: readonly ColonyChoice[] | undefined;
   isLoading: boolean;
   dataField?: string;
   describedBy?: string;
@@ -65,6 +129,9 @@ interface LivingColonySelectFieldProps {
  * Weak, conspicuous and queenless colonies are included - they need the most
  * attention - and none that has ended. A colony handed in by a link that has
  * ended since is still named, just not offered.
+ *
+ * Without network it offers the living colonies of the apiaries loaded for
+ * offline use ("Für offline laden") and says so.
  */
 export function LivingColonySelectField({
   triggerId,
@@ -76,18 +143,25 @@ export function LivingColonySelectField({
   emptyHint = "Noch keine aktiven Völker – zuerst unter „Völker“ eines anlegen.",
   dataField = "colonyId",
 }: LivingColonySelectFieldProps) {
-  const { data: colonies, isLoading, isError } = useColonies();
+  const { colonies, isLoading, hint: choicesHint } = useLivingColonyChoices();
   const living = colonies?.filter(
     (colony) => isLivingColony(colony) && colony.id !== excludeId,
   );
 
+  function hint(): string | undefined {
+    if (choicesHint) {
+      return HINT_TEXTS[choicesHint];
+    }
+    return living?.length === 0 ? emptyHint : undefined;
+  }
+
   return (
     <Field
       id={triggerId}
       label={label}
       required
       error={error}
-      hint={isError ? LOAD_ERROR_HINT : living?.length === 0 ? emptyHint : undefined}
+      hint={hint()}
     >
       {({ id, describedBy, invalid }) => (
         <ColonyChoices