test(pcap): run the missing-path refusal only where captures are admitted (#2510)

On hosts without an enforceable native bound (macOS), the provider refuses
inspect_pcap_capture with capability_unavailable before it touches the
path, which the unsupported-boundary test in the same file pins. The
missing-path test expected invalid_request on every host, so it always
failed on macOS while Linux and Windows CI stayed green.

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

tests/boundary/pcap/pcapProviderCrossPlatform.test.ts

@@ -87,17 +87,22 @@ it.runIf(hasNativeBound)(
   },
 );
 
-it("rejects a path that is not a readable file", async () => {
-  const result = await providerOver().execute({
-    operation: "inspect_pcap_capture",
-    input: { path: "/nonexistent/definitely-missing.pcap" },
-  });
-  expect(result.ok).toBe(false);
-  if (result.ok) return;
-  expect(projectAnalysisError(result.error)).toMatchObject({
-    code: "invalid_request",
-  });
-});
+// Hosts without a native bound refuse before touching the path; that order
+// is pinned by the unsupported-boundary test below.
+it.runIf(hasNativeBound)(
+  "rejects a path that is not a readable file",
+  async () => {
+    const result = await providerOver().execute({
+      operation: "inspect_pcap_capture",
+      input: { path: "/nonexistent/definitely-missing.pcap" },
+    });
+    expect(result.ok).toBe(false);
+    if (result.ok) return;
+    expect(projectAnalysisError(result.error)).toMatchObject({
+      code: "invalid_request",
+    });
+  },
+);
 
 it("reports a missing binary as a capability gap", async () => {
   const provider = new PcapProvider({