memory: harden LongMemEval methodology and provenance

Author: print-happy

.github/workflows/prc.yml

@@ -72,11 +72,10 @@ jobs:
           import subprocess
 
           source_root = "trpc.group/trpc-go/trpc-agent-go"
-          # The contributor fork hosts the stacked root support commit until
-          # that commit is merged upstream and the pin is updated.
+          expected_remote_root = "github.com/print-happy/trpc-agent-go"
+          expected_version = "v0.0.0-20260716032212-1b3adb2f4bb8"
           allowed_remote_roots = {
-              "github.com/trpc-group/trpc-agent-go",
-              "github.com/print-happy/trpc-agent-go",
+              expected_remote_root,
           }
           module = json.loads(
               subprocess.check_output(["go", "mod", "edit", "-json"])
@@ -114,7 +113,15 @@ jobs:
                   "trpc-agent-go replacements use different versions: "
                   + ", ".join(sorted(versions))
               )
-          print("trpc-agent-go dependency pin:", versions.pop())
+          version = versions.pop()
+          if pinned_roots != {expected_remote_root} or version != expected_version:
+              raise SystemExit(
+                  "unexpected trpc-agent-go dependency pin: "
+                  + ", ".join(sorted(pinned_roots))
+                  + "@"
+                  + version
+              )
+          print("trpc-agent-go dependency pin:", version)
           PY
       - name: Verify module dependencies
         working-directory: memory/trpc-agent-go-impl