feat: add read-only Social Accounts API

Add GET /api/accounts (list with optional ?network= and ?type= filters) and
GET /api/accounts/{socialAccount} (show) endpoints. Include plain-text password
field for AI agent consumption.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

app/Http/Controllers/Api/SocialAccountController.php

@@ -0,0 +1,31 @@
+<?php
+
+namespace App\Http\Controllers\Api;
+
+use App\Http\Controllers\Controller;
+use App\Http\Resources\SocialAccountResource;
+use App\Models\SocialAccount;
+use Illuminate\Http\Request;
+
+class SocialAccountController extends Controller
+{
+    public function index(Request $request)
+    {
+        $query = SocialAccount::query();
+
+        if ($request->filled('network')) {
+            $query->where('network', $request->string('network'));
+        }
+
+        if ($request->filled('type')) {
+            $query->where('type', $request->string('type'));
+        }
+
+        return SocialAccountResource::collection($query->orderBy('username')->get());
+    }
+
+    public function show(SocialAccount $socialAccount)
+    {
+        return new SocialAccountResource($socialAccount);
+    }
+}