Fix regex to span line breaks in shell-expansion guard detection

Co-authored-by: pelikhan <4175913+pelikhan@users.noreply.github.com>

Author: Copilot

actions/setup/js/detect_agent_errors.cjs

@@ -189,7 +189,7 @@ const MAX_CACHE_MISSES_EXCEEDED_PATTERN = /(?:\bmax_cache_misses_exceeded\b|\bma
 // This guard can misfire on benign multi-line printf/safeoutputs CLI invocations. Retrying the
 // identical command is pointless — it will be rejected again — so this is surfaced as a distinct,
 // actionable diagnostic instead of a generic shell failure.
-const SHELL_EXPANSION_GUARD_REJECTED_PATTERN = /could enable arbitrary code execution\b[^\n]{0,160}\brewrite the command without these expansion patterns\b/i;
+const SHELL_EXPANSION_GUARD_REJECTED_PATTERN = /could enable arbitrary code execution\b[\s\S]{0,200}?\brewrite the command without these expansion patterns\b/i;
 
 /**
  * Determines if the collected output contains the observed Copilot/CAPI quota exhaustion error.

actions/setup/js/detect_agent_errors.test.cjs

@@ -671,6 +671,11 @@ commentary" has no AI credits pricing`;
       expect(SHELL_EXPANSION_GUARD_REJECTED_PATTERN.test(ISSUE_REJECTION_MESSAGE.toUpperCase())).toBe(true);
     });
 
+    it("matches when the two anchor phrases are split across a line break", () => {
+      const wrapped = "Command rejected: ...that could enable arbitrary code execution.\nPlease rewrite the command without these expansion patterns.";
+      expect(isShellExpansionGuardRejectedError(wrapped)).toBe(true);
+    });
+
     it("does not match unrelated shell errors", () => {
       expect(isShellExpansionGuardRejectedError("bash: safeoutputs: command not found")).toBe(false);
       expect(isShellExpansionGuardRejectedError("permission denied by workflow tool permissions")).toBe(false);