Revert stream-binding approach: merge GET into the single MCP route instead

The second ai-mcp-proxy binding (added to fix the GET/SSE 502 loop)
created a second runtime plugin instance with the same tool config,
which ai-mcp-proxy's own duplicate-name detection caught: all three
tools (list-customers/get-customer/create-customer) fell back to
auto-generated names across both instances. Confirmed via dataplane
pod logs right after applying the previous fix.

Real fix: one KongRoute for all three MCP HTTP methods (GET/POST/
DELETE) instead of two, one ai-mcp-proxy binding instead of two.
ai-mcp-proxy already tolerates multi-method routes (same "skips
method selection" notice the existing POST+DELETE route already
produces) — extending to GET is the same class of thing, not new
risk, and there is now exactly one plugin instance so no duplicate
tool names.

kong/mcp/routes.yaml

@@ -1,3 +1,16 @@
+# Single route for all three MCP HTTP methods (GET opens the SSE stream,
+# POST carries JSON-RPC, DELETE terminates the session) — deliberately NOT
+# split into two KongRoutes the way catalog-mcp does. ai-mcp-proxy is bound
+# once, to this one route (mcp/pluginbindings.yaml); a second route with
+# its own binding of the *same* KongPlugin creates a second runtime plugin
+# instance with the same tool names, and ai-mcp-proxy's cross-instance
+# duplicate-name detection then falls back to auto-generated tool names
+# for all of them ("Tool custom name 'list-customers' already exists in
+# both plugin X and Y") — found and reverted 2026-08-23, see STATUS.md.
+# ai-mcp-proxy already tolerates a route with multiple methods (logs a
+# harmless "skips method selection" notice, same as catalog-mcp's existing
+# POST+DELETE route already does) — extending to GET here is the same
+# class of thing, not new risk.
 apiVersion: configuration.konghq.com/v1alpha1
 kind: KongRoute
 metadata:
@@ -12,6 +25,7 @@ spec:
   hosts:
     - ${REST_HOSTNAME}
   methods:
+    - GET
     - POST
     - DELETE
   paths:
@@ -19,24 +33,3 @@ spec:
   strip_path: false
   tags:
     - customers
----
-apiVersion: configuration.konghq.com/v1alpha1
-kind: KongRoute
-metadata:
-  name: ${NAME}-customers-mcp-stream
-  namespace: ${NAMESPACE}
-spec:
-  serviceRef:
-    type: namespacedRef
-    namespacedRef:
-      name: ${NAME}-customers-mcp
-  name: customers-mcp-stream
-  hosts:
-    - ${REST_HOSTNAME}
-  methods:
-    - GET
-  paths:
-    - /customers-mcp
-  strip_path: false
-  tags:
-    - customers