chore: import upstream snapshot with attribution

cmd/micro/web/main.js

@@ -0,0 +1,34 @@
+// Minimal JS for reactive form submissions
+
+document.addEventListener('DOMContentLoaded', function() {
+    document.querySelectorAll('form[data-reactive]')?.forEach(function(form) {
+        form.addEventListener('submit', async function(e) {
+            e.preventDefault();
+            const formData = new FormData(form);
+            const params = {};
+            for (const [key, value] of formData.entries()) {
+                params[key] = value;
+            }
+            const action = form.getAttribute('action');
+            const method = form.getAttribute('method') || 'POST';
+            try {
+                const resp = await fetch(action, {
+                    method,
+                    headers: { 'Content-Type': 'application/json' },
+                    body: JSON.stringify(params)
+                });
+                const data = await resp.json();
+                // Find or create a response container
+                let respDiv = form.querySelector('.js-response');
+                if (!respDiv) {
+                    respDiv = document.createElement('div');
+                    respDiv.className = 'js-response';
+                    form.appendChild(respDiv);
+                }
+                respDiv.innerHTML = '<pre>' + JSON.stringify(data, null, 2) + '</pre>';
+            } catch (err) {
+                alert('Error: ' + err);
+            }
+        });
+    });
+});