feat: CodePilot - desktop GUI for Claude Code

Full-featured desktop application built with Next.js + Electron:
- Streaming chat with Claude Code via Agent SDK
- Session management with SQLite persistence
- Project file tree and file preview
- MCP server and custom skills management
- Permission controls with Code/Plan/Ask modes
- Dark/light theme, token tracking
- macOS DMG packaging with electron-builder

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/app/api/settings/route.ts

@@ -0,0 +1,60 @@
+import { NextResponse } from "next/server";
+import fs from "fs";
+import path from "path";
+import os from "os";
+
+const SETTINGS_PATH = path.join(os.homedir(), ".claude", "settings.json");
+
+function readSettingsFile(): Record<string, unknown> {
+  try {
+    if (fs.existsSync(SETTINGS_PATH)) {
+      const content = fs.readFileSync(SETTINGS_PATH, "utf-8");
+      return JSON.parse(content);
+    }
+  } catch {
+    // Return empty object if file doesn't exist or is invalid
+  }
+  return {};
+}
+
+function writeSettingsFile(data: Record<string, unknown>): void {
+  const dir = path.dirname(SETTINGS_PATH);
+  if (!fs.existsSync(dir)) {
+    fs.mkdirSync(dir, { recursive: true });
+  }
+  fs.writeFileSync(SETTINGS_PATH, JSON.stringify(data, null, 2), "utf-8");
+}
+
+export async function GET() {
+  try {
+    const settings = readSettingsFile();
+    return NextResponse.json({ settings });
+  } catch (error) {
+    return NextResponse.json(
+      { error: "Failed to read settings" },
+      { status: 500 }
+    );
+  }
+}
+
+export async function PUT(request: Request) {
+  try {
+    const body = await request.json();
+    const { settings } = body;
+
+    if (!settings || typeof settings !== "object") {
+      return NextResponse.json(
+        { error: "Invalid settings data" },
+        { status: 400 }
+      );
+    }
+
+    writeSettingsFile(settings);
+    return NextResponse.json({ success: true });
+  } catch (error) {
+    return NextResponse.json(
+      { error: "Failed to save settings" },
+      { status: 500 }
+    );
+  }
+}