Add Clear Data button to wipe county data folders

web/templates/index.html

@@ -376,6 +376,7 @@
         <h1>OSM Import Tools</h1>
         <div class="topbar-sep"></div>
         <button class="btn-topbar" onclick="runScript('ls', '')">List Files</button>
+        <button class="btn-topbar" onclick="clearData()" style="color:#f88;">Clear Data</button>
         <div style="flex:1"></div>
         <div class="config-group">
             <a href="/api/config/counties.yml" class="btn-topbar-icon" title="Download counties.yml">↓ counties.yml</a>
@@ -725,6 +726,21 @@
         .finally(() => enableButtons());
     }
 
+    function clearData() {
+        if (!confirm('Delete all downloaded and processed files from all county folders?')) return;
+        fetch('/api/clear-data', { method: 'POST' })
+        .then(r => r.json())
+        .then(data => {
+            if (data.error) {
+                showStatus(`Error: ${data.error}`, 'error');
+            } else {
+                showStatus(`Cleared ${data.removed.length} file(s).`, 'success');
+                setTimeout(() => window.location.reload(), 800);
+            }
+        })
+        .catch(err => showStatus(`Error: ${err.message}`, 'error'));
+    }
+
     function uploadConfig(filename, input) {
         if (!input.files.length) return;
         const formData = new FormData();