Wire the composition root: flags, providers, runnables, manifests, samples, docs

Co-Authored-By: Claude <noreply@anthropic.com>

config/samples/proxy_external.yaml

@@ -0,0 +1,15 @@
+# An External proxy: the VM exists outside the operator's control; the
+# operator only tracks and health-checks it through the endpoint. No
+# finalizer, no provider calls, and deleting the CR touches nothing.
+apiVersion: crawl.example.com/v1alpha1
+kind: Proxy
+metadata:
+  name: proxy-external-sample
+spec:
+  mode: External
+  endpoint:
+    host: 203.0.113.7
+    port: 3128
+  attributes:
+    geo: eu
+    purpose: crawl