feat(validator): manifest-validator (F02) + bad-manifest фикстуры (F04)

Правила: id не ru.shturman.*, shturman_api поддержан, len(tiles)<=ui_tiles, vehicle_read из каталога.
Фикстуры good + bad-{id-reserved,api,tiles-quota,vehicle-read}; 6 тестов.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Signed-off-by: Alexander <akotenev2003@gmail.com>

fixtures/manifests/bad-tiles-quota.yaml

@@ -0,0 +1,14 @@
+# Тайлов больше, чем квота ui_tiles (plugin-sdk §2).
+plugin:
+  id: dev.example.greedy
+  name: "Жадный"
+  version: 0.1.0
+  shturman_api: "1"
+capabilities:
+  ui_tiles: 1
+extension_points:
+  tiles:
+    - id: a
+      title: "A"
+    - id: b
+      title: "B"