fix: remove name-based fallback for seed control_after_generate

Remove name-based inference in useIntWidget.ts and groupNode.ts that
auto-added control_after_generate for any INT input named "seed" or
"noise_seed". Now only adds the control widget when control_after_generate
is explicitly set by the backend.

All core backend nodes already set control_after_generate explicitly.
Custom nodes like WAS_Text_Random_Line that use "seed" as a plain INT
were incorrectly getting a randomize control widget that reset on every
tab switch (since the control widget has serialize: false).

Update test fixture and remove stale screenshot expectation for the
DevToolsNodeWithSeedInput test node, which correctly has no
control_after_generate.

Fixes #7468

browser_tests/assets/widgets/seed_widget.json

@@ -15,7 +15,7 @@
       "properties": {
         "Node name for S&R": "DevToolsNodeWithSeedInput"
       },
-      "widgets_values": [0, "randomize"]
+      "widgets_values": [0]
     }
   ],
   "links": [],