Add browser extension gRPC bridge

browser/extension/options.js

@@ -0,0 +1,47 @@
+const extOptions = globalThis.browser ?? globalThis.chrome;
+
+function runtimeSend(message) {
+  return new Promise((resolve, reject) => {
+    extOptions.runtime.sendMessage(message, (response) => {
+      const error = extOptions.runtime.lastError;
+      if (error) {
+        reject(new Error(error.message));
+        return;
+      }
+      resolve(response);
+    });
+  });
+}
+
+async function loadSettings() {
+  const response = await runtimeSend({ type: "keepassgo-load-settings" });
+  if (!response?.success) {
+    throw new Error(response?.error || "Could not load settings.");
+  }
+  document.getElementById("grpc-address").value = response.settings.grpcAddress || "127.0.0.1:47777";
+  document.getElementById("bearer-token").value = response.settings.bearerToken || "";
+}
+
+async function saveSettings(event) {
+  event.preventDefault();
+  const status = document.getElementById("settings-status");
+  status.textContent = "Saving…";
+  try {
+    const response = await runtimeSend({
+      type: "keepassgo-save-settings",
+      settings: {
+        grpcAddress: document.getElementById("grpc-address").value,
+        bearerToken: document.getElementById("bearer-token").value
+      }
+    });
+    if (!response?.success) {
+      throw new Error(response?.error || "Could not save settings.");
+    }
+    status.textContent = "Saved.";
+  } catch (error) {
+    status.textContent = error instanceof Error ? error.message : String(error);
+  }
+}
+
+document.getElementById("settings-form").addEventListener("submit", saveSettings);
+void loadSettings();