fix(cli): protect Go install credentials

cmd/elydora/plugins/runtime_reader_template.go

@@ -0,0 +1,48 @@
+package plugins
+
+import "fmt"
+
+var protectedRuntimeFileReader = fmt.Sprintf(`const MAX_PROTECTED_SECRET_BYTES = %d;
+const MAX_PROTECTED_CONFIG_BYTES = %d;
+
+function readProtectedFile(filePath, label, maxBytes = MAX_PROTECTED_SECRET_BYTES) {
+  const before = fs.lstatSync(filePath);
+  if (!before.isFile() || before.isSymbolicLink()) {
+    throw new Error(label + ' path is not a physical file: ' + filePath);
+  }
+  if (before.size > maxBytes) {
+    throw new Error(label + ' exceeds the size limit: ' + filePath);
+  }
+  if (process.platform !== 'win32' && (before.mode & 0o077) !== 0) {
+    throw new Error(label + ' permissions are too broad: ' + filePath);
+  }
+
+  let flags = fs.constants.O_RDONLY;
+  if (process.platform !== 'win32' && typeof fs.constants.O_NOFOLLOW === 'number') {
+    flags |= fs.constants.O_NOFOLLOW;
+  }
+  const descriptor = fs.openSync(filePath, flags);
+  try {
+    const after = fs.fstatSync(descriptor);
+    if (!after.isFile()) {
+      throw new Error(label + ' path is not a physical file: ' + filePath);
+    }
+    if (after.size > maxBytes) {
+      throw new Error(label + ' exceeds the size limit: ' + filePath);
+    }
+    if (process.platform !== 'win32' && (after.mode & 0o077) !== 0) {
+      throw new Error(label + ' permissions are too broad: ' + filePath);
+    }
+    if (before.dev !== after.dev || before.ino !== after.ino) {
+      throw new Error(label + ' changed while opening: ' + filePath);
+    }
+    const raw = fs.readFileSync(descriptor);
+    if (raw.length > maxBytes) {
+      throw new Error(label + ' exceeds the size limit: ' + filePath);
+    }
+    return raw;
+  } finally {
+    fs.closeSync(descriptor);
+  }
+}
+`, maxProtectedSecretBytes, maxRuntimeConfigBytes)