feat: bundle provider auth plugins

Co-authored-by: ItzR3NO <ItzR3NO@users.noreply.github.com>

src/plugins/bundled-dir.ts

@@ -0,0 +1,33 @@
+import fs from "node:fs";
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+
+export function resolveBundledPluginsDir(): string | undefined {
+  const override = process.env.CLAWDBOT_BUNDLED_PLUGINS_DIR?.trim();
+  if (override) return override;
+
+  // bun --compile: ship a sibling `extensions/` next to the executable.
+  try {
+    const execDir = path.dirname(process.execPath);
+    const sibling = path.join(execDir, "extensions");
+    if (fs.existsSync(sibling)) return sibling;
+  } catch {
+    // ignore
+  }
+
+  // npm/dev: walk up from this module to find `extensions/` at the package root.
+  try {
+    let cursor = path.dirname(fileURLToPath(import.meta.url));
+    for (let i = 0; i < 6; i += 1) {
+      const candidate = path.join(cursor, "extensions");
+      if (fs.existsSync(candidate)) return candidate;
+      const parent = path.dirname(cursor);
+      if (parent === cursor) break;
+      cursor = parent;
+    }
+  } catch {
+    // ignore
+  }
+
+  return undefined;
+}