feat(block1): inventory walking skeleton + first quick-add slice

Stand up the Tanemaki monorepo and the first end-to-end vertical slice of
Block 1 (offline, encrypted inventory): add a seed → see it in a categorized,
searchable list → it persists → reopen and it's still there.

Architecture (state management like G1nkgo, adapted to Tane's reality):
- flutter_bloc (Cubit-first), but the encrypted Drift DB is the single source
  of truth; cubits stream from repositories (no hydrated_bloc/Hive, which would
  write plaintext at rest).
- get_it composition root; go_router; slang i18n (ES/EN, Weblate-friendly JSON).

Workspace & core:
- pub workspace: packages/commons_core (pure Dart) + apps/app_seeds (Flutter).
- commons_core primitives: UUIDv7 IdGen, Hybrid Logical Clock, Quantity value
  type (+ plant-aware QuantityKind), IdentityService root-seed stub.

Data & security:
- Drift schemaVersion=1 with all 10 Block-1 tables + common CRDT columns
  (HLC updated_at, last_author, tombstones); Movement append-only.
- SQLCipher via an injectable executor that refuses to open a plaintext DB;
  DB key + root seed in the OS keystore (separate secrets).
- Exported drift_schema_v1.json + migration scaffold.

Tests (near-TDD; nothing merges without tests):
- commons_core units (24), Drift migration test, "no plaintext at rest"
  security guard (runs where SQLCipher is present, skips otherwise),
  repository, widget, full quick-add flow, file-reopen persistence, and a
  no-hardcoded-strings i18n guard. GitLab CI: format + analyze + test + coverage.

Follow-on Block-1 stories (item detail/edit, species catalog, germination UI)
and all of Block 2 remain out of scope.

apps/app_seeds/test/data/persistence_test.dart

@@ -0,0 +1,37 @@
+import 'dart:io';
+
+import 'package:commons_core/commons_core.dart';
+import 'package:drift/native.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:path/path.dart' as p;
+import 'package:tane/data/variety_repository.dart';
+import 'package:tane/db/database.dart';
+
+/// Proves the "reopen and it's still there" half of the sprint's definition of
+/// done at the persistence layer, on a real on-disk file (unencrypted here so
+/// it runs on any host — encryption at rest is covered by no_plaintext_test).
+void main() {
+  test('a seed survives closing and reopening the database file', () async {
+    final dir = await Directory.systemTemp.createTemp('tane_persist');
+    addTearDown(() => dir.delete(recursive: true));
+    final file = File(p.join(dir.path, 'inventory.sqlite'));
+
+    var db = AppDatabase(NativeDatabase(file));
+    await VarietyRepository(
+      db,
+      idGen: IdGen(),
+      nodeId: 'n',
+    ).addQuickVariety(label: 'Persisted tomato');
+    await db.close();
+
+    db = AppDatabase(NativeDatabase(file));
+    final items = await VarietyRepository(
+      db,
+      idGen: IdGen(),
+      nodeId: 'n',
+    ).watchInventory().first;
+    await db.close();
+
+    expect(items.map((i) => i.label), ['Persisted tomato']);
+  });
+}