Remove Supabase

The database moved to a container of our own; the platform is gone.
This takes out what was left of it — and, where the leftovers were load
bearing, moves rather than deletes.

Moved, not deleted:

  supabase/migrations/  -> db/migrations/      the schema's source of truth
  supabase/build-org.ts -> scripts/build-org.ts
  lib/supabase/types.ts -> lib/types.ts        52 import sites repointed

The bookkeeping needed care. It lived in `supabase_migrations.schema_migrations`,
and simply renaming the schema would have left the runner facing an empty
table: it would have called all 67 migrations pending and replayed them
against a database that is long since current. So the runner now creates
`migrationen.schema_migrations` and, once, copies the old rows across —
guarded so a second run does nothing and a fresh database skips it entirely.
Only then does migration 20260907100000 drop the old schema.

Deleted: the CLI config, the seed, the historical schema/function dumps
(nothing read them), scripts/umzug-von-supabase.sh (the move is done), and
both Supabase packages plus the CLI. Nothing in the application imported
them — the build now succeeds with no environment variables at all, which
is the proof.

Integration tests: six of them signed in through Supabase Auth and asserted
against the anon key and the service role. That model is gone, so the tests
were not portable — they are deleted. session-context and
employee-status-filter already ran on pg and are untouched; om-reporting is
ported to a direct connection because it guards a real risk (the reporting
line rule exists twice, once in SQL and once in TypeScript).

CI: the integration job started a Supabase stack. It now runs a postgres
service, applies deploy/db-init and every migration to an empty database —
that was the valuable part, and it still holds — then checks that a second
run is a no-op, which is what proves the bookkeeping works.

Docs: security-review.md audited a service-role key, a cookie adapter and
auth.users, none of which exist. Restating findings about removed components
would suggest today's system had been reviewed; it has not. It now records
what was removed and says a fresh review is due. data-model.md was already
marked obsolete and described the pre-OM schema; azure-migration.md was a
plan for a route not taken. Both deleted.

Verified: npm ci, typecheck, lint, 445 tests, build — all clean without the
packages. Integration tests skip cleanly with no database. Migration SQL and
the runner are reviewed but NOT executed: no Docker here, and the old
instance no longer resolves.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

db/migrations/20260805120000_fix_hire_employee_precedence.sql

@@ -0,0 +1,66 @@
+-- Klammern in hire_employee.
+--
+-- Der Protokolleintrag baute den Namen so:
+--
+--     payload->>'first_name' || ' ' || payload->>'last_name'
+--
+-- In PostgreSQL bindet `||` **stärker** als `->>`. Gelesen wird also
+--
+--     payload ->> ('first_name' || ' ' || payload) ->> 'last_name'
+--
+-- und das endet in „operator does not exist: text ->> unknown". Jede
+-- Neueinstellung scheiterte daran.
+--
+-- Warum es niemandem auffiel: davor stand in derselben Anweisung ein Aufruf
+-- von auth.uid(). Die Rechteprüfung auf das Schema `auth` schlug schon
+-- während der Analyse fehl, und der Parser kam nie bis zu diesem Ausdruck.
+-- Ein Fehler hat den anderen verdeckt — beide mussten weg, damit eine
+-- Einstellung durchläuft.
+
+do $$
+declare
+  v_def text;
+  v_alt constant text := 'payload->>''first_name'' || '' '' || payload->>''last_name''';
+  v_neu constant text := '(payload->>''first_name'') || '' '' || (payload->>''last_name'')';
+begin
+  select pg_get_functiondef(p.oid) into v_def
+    from pg_proc p
+    join pg_namespace n on n.oid = p.pronamespace
+   where n.nspname = 'public' and p.proname = 'hire_employee'
+   limit 1;
+
+  if v_def is null then
+    raise exception 'hire_employee() nicht gefunden.';
+  end if;
+
+  if position(v_alt in v_def) = 0 then
+    raise notice 'hire_employee(): bereits geklammert.';
+  else
+    execute replace(v_def, v_alt, v_neu);
+    raise notice 'hire_employee(): geklammert.';
+  end if;
+end;
+$$;
+
+-- ═══ Gegenprobe ══════════════════════════════════════════════════
+-- Der Ausdruck selbst, in beiden Lesarten. Ohne Klammern wirft er; mit
+-- Klammern kommt der Name heraus. Das hält die Regel fest, damit sie beim
+-- nächsten Mal nicht neu entdeckt werden muss.
+do $$
+declare
+  v_payload jsonb := '{"first_name": "Anna", "last_name": "Berger"}'::jsonb;
+  v_name text;
+begin
+  v_name := (v_payload->>'first_name') || ' ' || (v_payload->>'last_name');
+  if v_name <> 'Anna Berger' then
+    raise exception 'Geklammert ergibt „%" statt „Anna Berger".', v_name;
+  end if;
+
+  begin
+    execute $probe$ select ('{"a":"x"}'::jsonb)->>'a' || ' ' || ('{"a":"x"}'::jsonb)->>'a' $probe$;
+    raise exception 'Ungeklammert wirft nicht mehr — die Vorrangregel hat sich geändert, die Prüfung ist wertlos geworden.';
+  exception
+    when undefined_function then null;  -- erwartet: text ->> unknown
+  end;
+end;
+$$;