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.

packages/commons_core/test/clock/hlc_test.dart

@@ -0,0 +1,91 @@
+import 'package:commons_core/commons_core.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group('Hlc', () {
+    test('round-trips through pack/parse', () {
+      const h = Hlc(millis: 1720000000000, counter: 7, nodeId: 'node-a');
+      expect(Hlc.parse(h.pack()), h);
+    });
+
+    test('parse tolerates a nodeId containing colons', () {
+      const h = Hlc(millis: 42, counter: 1, nodeId: 'a:b:c');
+      expect(Hlc.parse(h.pack()), h);
+    });
+
+    test('packed form sorts lexically in timestamp order', () {
+      const older = Hlc(millis: 100, counter: 9, nodeId: 'z');
+      const newer = Hlc(millis: 200, counter: 0, nodeId: 'a');
+      expect(older.pack().compareTo(newer.pack()), lessThan(0));
+    });
+
+    test('packed counter breaks ties within the same millisecond', () {
+      const a = Hlc(millis: 100, counter: 1, nodeId: 'n');
+      const b = Hlc(millis: 100, counter: 2, nodeId: 'n');
+      expect(a.pack().compareTo(b.pack()), lessThan(0));
+    });
+
+    group('localEvent', () {
+      test(
+        'advances millis and resets counter when wall clock moves forward',
+        () {
+          const clock = Hlc(millis: 100, counter: 4, nodeId: 'n');
+          final next = clock.localEvent(200);
+          expect(next.millis, 200);
+          expect(next.counter, 0);
+        },
+      );
+
+      test('bumps counter when wall clock is unchanged', () {
+        const clock = Hlc(millis: 100, counter: 4, nodeId: 'n');
+        final next = clock.localEvent(100);
+        expect(next.millis, 100);
+        expect(next.counter, 5);
+      });
+
+      test('stays monotonic when the wall clock runs backwards', () {
+        const clock = Hlc(millis: 100, counter: 4, nodeId: 'n');
+        final next = clock.localEvent(50); // clock skew
+        expect(next.millis, 100);
+        expect(next.counter, 5);
+        expect(next.compareTo(clock), greaterThan(0));
+      });
+    });
+
+    group('receiveEvent', () {
+      test('takes the max millis and bumps beyond both counters on a tie', () {
+        const local = Hlc(millis: 100, counter: 2, nodeId: 'local');
+        const remote = Hlc(millis: 100, counter: 5, nodeId: 'remote');
+        final merged = local.receiveEvent(remote, 100);
+        expect(merged.millis, 100);
+        expect(merged.counter, 6);
+        expect(merged.nodeId, 'local'); // identity stays local
+      });
+
+      test('adopts a remote future timestamp and continues its counter', () {
+        const local = Hlc(millis: 100, counter: 2, nodeId: 'local');
+        const remote = Hlc(millis: 300, counter: 1, nodeId: 'remote');
+        final merged = local.receiveEvent(remote, 120);
+        expect(merged.millis, 300);
+        expect(merged.counter, 2);
+      });
+
+      test('resets counter when the wall clock leads everything', () {
+        const local = Hlc(millis: 100, counter: 2, nodeId: 'local');
+        const remote = Hlc(millis: 150, counter: 9, nodeId: 'remote');
+        final merged = local.receiveEvent(remote, 400);
+        expect(merged.millis, 400);
+        expect(merged.counter, 0);
+      });
+    });
+
+    test('compareTo orders by millis, then counter, then nodeId', () {
+      const a = Hlc(millis: 1, counter: 0, nodeId: 'a');
+      const b = Hlc(millis: 1, counter: 0, nodeId: 'b');
+      const c = Hlc(millis: 1, counter: 1, nodeId: 'a');
+      const d = Hlc(millis: 2, counter: 0, nodeId: 'a');
+      final sorted = [d, c, b, a]..sort();
+      expect(sorted, [a, b, c, d]);
+    });
+  });
+}