feat: add low-cardinality observation port

tests/fixtures/architecture/dependency-baseline.json

@@ -13,8 +13,8 @@
     "runtime_to_db": [],
     "workflow_to_db": []
   },
-  "edge_count": 6232,
-  "edge_sha256": "2139dcdcfc12b4f29c732471744d09b0990c51867d4ad227026b00fa947c90d8",
+  "edge_count": 6244,
+  "edge_sha256": "f187bdbb5e88ce9a6b2ff559b10e5e6cd5a60d14693484ea17663cebf438cc92",
   "edges": [
     "app -> app.runtime",
     "app -> app.runtime.compat",
@@ -106,6 +106,8 @@
     "app.adapters.network.doh -> app.runtime.reload",
     "app.adapters.network.http -> app.runtime",
     "app.adapters.network.http -> app.runtime.correlation",
+    "app.adapters.observability.otel -> app.runtime",
+    "app.adapters.observability.otel -> app.runtime.observability",
     "app.adapters.system.display -> app.foundation",
     "app.adapters.system.display -> app.foundation.singleton",
     "app.adapters.system.display -> app.runtime",
@@ -157,6 +159,8 @@
     "app.adapters.web.correlation -> app.runtime.correlation",
     "app.adapters.web.health -> app.runtime",
     "app.adapters.web.health -> app.runtime.health",
+    "app.adapters.web.metrics -> app.runtime",
+    "app.adapters.web.metrics -> app.runtime.observability",
     "app.adapters.web.security.access -> app.runtime",
     "app.adapters.web.security.access -> app.runtime.cache",
     "app.adapters.web.security.access -> app.runtime.config",
@@ -3722,9 +3726,12 @@
     "app.domain.title -> app.schemas",
     "app.domain.title -> app.schemas.types",
     "app.factory -> app.adapters",
+    "app.factory -> app.adapters.observability",
+    "app.factory -> app.adapters.observability.otel",
     "app.factory -> app.adapters.web",
     "app.factory -> app.adapters.web.correlation",
     "app.factory -> app.adapters.web.health",
+    "app.factory -> app.adapters.web.metrics",
     "app.factory -> app.adapters.web.plugin",
     "app.factory -> app.adapters.web.plugin.routes",
     "app.factory -> app.adapters.web.security",
@@ -3743,6 +3750,7 @@
     "app.factory -> app.runtime.extensions.plugin_manager",
     "app.factory -> app.runtime.localization",
     "app.factory -> app.runtime.log",
+    "app.factory -> app.runtime.observability",
     "app.factory -> app.schemas",
     "app.factory -> app.schemas.mcp",
     "app.factory -> app.schemas.openai",
@@ -5365,6 +5373,7 @@
     "app.runtime.event.dispatch -> app.runtime.event.registry",
     "app.runtime.event.dispatch -> app.runtime.execution",
     "app.runtime.event.dispatch -> app.runtime.log",
+    "app.runtime.event.dispatch -> app.runtime.observability",
     "app.runtime.event.dispatch -> app.schemas",
     "app.runtime.event.dispatch -> app.schemas.types",
     "app.runtime.event.errors -> app.runtime",
@@ -5387,6 +5396,7 @@
     "app.runtime.events -> app.runtime.event.errors",
     "app.runtime.events -> app.runtime.event.registry",
     "app.runtime.events -> app.runtime.log",
+    "app.runtime.events -> app.runtime.observability",
     "app.runtime.events -> app.runtime.rate",
     "app.runtime.events -> app.runtime.thread",
     "app.runtime.events -> app.schemas",
@@ -5417,6 +5427,7 @@
     "app.runtime.extensions.module.dispatcher -> app.runtime.extensions.module",
     "app.runtime.extensions.module.dispatcher -> app.runtime.extensions.module.contracts",
     "app.runtime.extensions.module.dispatcher -> app.runtime.log",
+    "app.runtime.extensions.module.dispatcher -> app.runtime.observability",
     "app.runtime.extensions.module.dispatcher -> app.schemas",
     "app.runtime.extensions.module.dispatcher -> app.schemas.exception",
     "app.runtime.extensions.module_manager -> app.foundation",
@@ -5573,6 +5584,7 @@
     "app.scheduler -> app.runtime.extensions.service_config",
     "app.scheduler -> app.runtime.gc",
     "app.scheduler -> app.runtime.log",
+    "app.scheduler -> app.runtime.observability",
     "app.scheduler -> app.runtime.progress",
     "app.scheduler -> app.runtime.reload",
     "app.scheduler -> app.runtime.scheduling",
@@ -6249,7 +6261,7 @@
     "app.workflow.actions.transfer_file -> app.workflow",
     "app.workflow.actions.transfer_file -> app.workflow.actions"
   ],
-  "module_count": 778,
+  "module_count": 782,
   "modules": [
     "app",
     "app.adapters",
@@ -6271,6 +6283,8 @@
     "app.adapters.network.doh",
     "app.adapters.network.http",
     "app.adapters.network.ip",
+    "app.adapters.observability",
+    "app.adapters.observability.otel",
     "app.adapters.system",
     "app.adapters.system.backup",
     "app.adapters.system.backup.database",
@@ -6291,6 +6305,7 @@
     "app.adapters.web",
     "app.adapters.web.correlation",
     "app.adapters.web.health",
+    "app.adapters.web.metrics",
     "app.adapters.web.plugin",
     "app.adapters.web.plugin.routes",
     "app.adapters.web.security",
@@ -6922,6 +6937,7 @@
     "app.runtime.localization",
     "app.runtime.log",
     "app.runtime.managed_resources",
+    "app.runtime.observability",
     "app.runtime.progress",
     "app.runtime.rate",
     "app.runtime.reload",