Add -count=1 to the canonical Go make test example (closes #44)

The canonical Go `test` target in `REPO_POLICIES.md` omitted `-count=1`, so
Go replayed cached successful results and the target could exit 0 having
executed no test. Every repo that copied it inherited the false green.

Both invocations get the flag; the rerun needs it so a failure is
reproduced rather than replayed.

prompts/REPO_POLICIES.md

@@ -1,6 +1,6 @@
 ---
 title: Repository Policies
-last_modified: 2026-08-07
+last_modified: 2026-08-10
 ---
 
 This document covers repository structure, tooling, and workflow standards. Code
@@ -209,11 +209,16 @@ style conventions are in separate documents:
 
     ```makefile
     test:
-    	@go test -timeout 30s -race -cover ./... || \
+    	@go test -count=1 -timeout 30s -race -cover ./... || \
     		{ echo "--- Rerunning with -v for details ---"; \
-    		  go test -timeout 30s -race -v ./...; exit 1; }
+    		  go test -count=1 -timeout 30s -race -v ./...; exit 1; }
     ```
 
+    `-count=1` is required on both invocations: it defeats Go's test _result_
+    cache, so the target cannot report a pass it did not earn, and the rerun
+    reproduces a failure instead of replaying it. It leaves the build cache
+    alone, so it costs the runtime of the suite and no recompilation.
+
     Python example:
 
     ```makefile