Feat: implement callback for TwitterAPI linking

callback/twitter.js

@@ -0,0 +1,37 @@
+async function finalizeLink() {
+    const urlParams = new URLSearchParams(window.location.search);
+    const code = urlParams.get('code');
+    const state = urlParams.get('state');
+
+    const statusDiv = document.getElementById('status');
+
+    if (!code || !state) {
+        statusDiv.innerHTML = "<h2>Error: Missing data from Twitter</h2>";
+        return;
+    }
+
+    try {
+        const response = await fetch(`/api/v1/me/twitter/confirm?state=${state}&code=${code}`, {
+            method: 'GET',
+        });
+
+        const data = await response.json();
+
+        if (response.ok) {
+            statusDiv.innerHTML = `
+                <h2>Success!</h2>
+                <p>Linked as @${data.handle}</p>
+                <p>Redirecting you back...</p>
+            `;
+            setTimeout(() => {
+                window.location.href = '/';
+            }, 2000);
+        } else {
+            statusDiv.innerHTML = `<h2>Error: ${data.detail || 'Failed to link'}</h2>`;
+        }
+    } catch (err) {
+        statusDiv.innerHTML = "<h2>Failed to connect to backend</h2>";
+    }
+}
+
+finalizeLink();