phase 4: drop stale gRPC nomenclature from integration tests

Phase 4 replaced the gateway's authenticated edge listener with a
Connect-Go HTTP/h2c bootstrap that natively serves Connect, gRPC,
and gRPC-Web. Sweep the integration suite so test names, comments,
and helper docs match the new transport posture: rename
TestUserAccount_GetThroughGatewayGRPC to TestUserAccount_GetThroughGatewayEdge,
flip "authenticated gRPC" / "signed gRPC" / "gateway gRPC" comments
to "authenticated edge", and align testenv doc strings.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

integration/user_account_test.go

@@ -11,9 +11,9 @@ import (
 	"galaxy/transcoder"
 )
 
-// TestUserAccount_GetThroughGatewayGRPC drives the authenticated
-// gRPC user surface (`user.account.get`) through gateway → backend
-// → user store. The test signs an envelope, sends it via gRPC, and
+// TestUserAccount_GetThroughGatewayEdge drives the authenticated
+// edge user surface (`user.account.get`) through gateway → backend
+// → user store. The test signs an envelope, sends it via Connect, and
 // verifies the response signature, then decodes the FlatBuffers
 // payload into the typed AccountResponse.
 //
@@ -21,7 +21,7 @@ import (
 // backend's HTTP `/api/v1/user/account`, which triggers the geo
 // counter middleware. We validate the counter increments on the
 // admin geo endpoint.
-func TestUserAccount_GetThroughGatewayGRPC(t *testing.T) {
+func TestUserAccount_GetThroughGatewayEdge(t *testing.T) {
 	plat := testenv.Bootstrap(t, testenv.BootstrapOptions{})
 	ctx, cancel := context.WithTimeout(context.Background(), 60*time.Second)
 	defer cancel()