refactor: unify plugin runtime access

tests/fixtures/architecture/dependency-baseline.json

@@ -14,7 +14,7 @@
     "workflow_to_db": []
   },
   "edge_count": 6500,
-  "edge_sha256": "7afa6e61ca564c1ec0c5981304cdb219afa99eb3318bb1703e8acf363cab9aae",
+  "edge_sha256": "d143f65c278b6eb1887240583c9ecce7b17a8cf7931a22b4f4cd39f269ac676c",
   "edges": [
     "app -> app.runtime",
     "app -> app.runtime.compat",
@@ -3880,12 +3880,11 @@
     "app.factory -> app.application",
     "app.factory -> app.application.plugin",
     "app.factory -> app.application.plugin.routes",
+    "app.factory -> app.application.plugin.runtime",
     "app.factory -> app.application.security",
     "app.factory -> app.application.security.token",
     "app.factory -> app.runtime",
     "app.factory -> app.runtime.correlation",
-    "app.factory -> app.runtime.extensions",
-    "app.factory -> app.runtime.extensions.plugin_manager",
     "app.factory -> app.runtime.localization",
     "app.factory -> app.runtime.log",
     "app.factory -> app.runtime.observability",
@@ -5764,6 +5763,8 @@
     "app.scheduler -> app.application.messaging",
     "app.scheduler -> app.application.messaging.message",
     "app.scheduler -> app.application.outbox",
+    "app.scheduler -> app.application.plugin",
+    "app.scheduler -> app.application.plugin.runtime",
     "app.scheduler -> app.application.scheduling",
     "app.scheduler -> app.application.site",
     "app.scheduler -> app.chain",
@@ -5783,7 +5784,6 @@
     "app.scheduler -> app.runtime.correlation",
     "app.scheduler -> app.runtime.events",
     "app.scheduler -> app.runtime.extensions",
-    "app.scheduler -> app.runtime.extensions.plugin_manager",
     "app.scheduler -> app.runtime.extensions.service_config",
     "app.scheduler -> app.runtime.gc",
     "app.scheduler -> app.runtime.log",