make c, cpp and rust plugins as well as their builders (thank you claude). Also add support for multi lang plugins so that we can actually fucking unload them unlike shitty golang (issue has been opened since 2015 and there is no due date for the issue...)

plugin-sample-cpp/sample-cpp.html

@@ -0,0 +1,42 @@
+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1" />
+    <title>Sample C++ Plugin</title>
+    <link rel="stylesheet" href="/plugins/sample-cpp/assets/sample-cpp.css" />
+  </head>
+  <body>
+    <main class="container">
+      <header class="header">
+        <h1>Sample C++ Plugin</h1>
+        <p class="sub">C++ &mdash; fully unloadable, zero runtime leak</p>
+      </header>
+
+      <section class="card">
+        <div class="row">
+          <label class="label">Client ID</label>
+          <input id="client-id" class="input" placeholder="clientId" />
+        </div>
+
+        <div class="row">
+          <label class="label">Message</label>
+          <input id="message" class="input" placeholder="hello from UI" />
+        </div>
+
+        <div class="actions">
+          <button id="send-btn" class="btn">Send event to client</button>
+          <button id="ping-btn" class="btn">Ping</button>
+          <button id="stats-btn" class="btn">Get Stats</button>
+        </div>
+      </section>
+
+      <section class="card">
+        <h2>Log</h2>
+        <pre id="log" class="log"></pre>
+      </section>
+    </main>
+
+    <script src="/plugins/sample-cpp/assets/sample-cpp.js"></script>
+  </body>
+</html>