fix: preserve dns pinning for strict web SSRF fetches

src/slack/send.ts

@@ -220,6 +220,7 @@ async function uploadSlackFile(params: {
     },
     policy: SLACK_UPLOAD_SSRF_POLICY,
     proxy: "env",
+    dangerouslyAllowEnvProxyWithoutPinnedDns: true,
     auditContext: "slack-upload-file",
   });
   try {

src/slack/send.upload.test.ts

@@ -168,6 +168,7 @@ describe("sendMessageSlack file upload with user IDs", () => {
       expect.objectContaining({
         url: "https://uploads.slack.test/upload",
         proxy: "env",
+        dangerouslyAllowEnvProxyWithoutPinnedDns: true,
         auditContext: "slack-upload-file",
       }),
     );