Add CSV upload for references

index.html

@@ -51,7 +51,8 @@
   <!-- ── Bulk edit popover ─────────────────────────────────────── -->
   <div id="bulk-edit-popover" hidden>
     <button id="btn-open-bulk-refs">📎 Bulk Edit References</button>
-    <button id="btn-upload-csv">📂 Upload from CSV</button>
+    <button id="btn-upload-csv">📂 Upload Tunes from CSV</button>
+    <button id="btn-upload-refs-csv">🔗 Upload References from CSV</button>
   </div>
 
   <!-- ── Bulk edit references modal ───────────────────────────── -->
@@ -255,6 +256,36 @@
     </div>
   </dialog>
 
+  <!-- ── References CSV upload modal ───────────────────────────── -->
+  <dialog id="upload-refs-csv-modal">
+    <h2>Upload References from CSV</h2>
+    <details id="refs-csv-format-details" open>
+      <summary>Expected format</summary>
+      <p style="font-size:.85rem;margin:.5rem 0 .4rem">One reference per row. Tune matched by name — must already exist.</p>
+      <table class="csv-format-table">
+        <thead><tr><th>Column</th><th>Required</th><th>Notes</th></tr></thead>
+        <tbody>
+          <tr><td>tune_name</td><td>Yes</td><td>Must match an existing tune (case-insensitive)</td></tr>
+          <tr><td>link</td><td></td><td>URL</td></tr>
+          <tr><td>site</td><td></td><td>Site name — created if new</td></tr>
+          <tr><td>musician1</td><td></td><td>Musician name — created if new</td></tr>
+          <tr><td>musician2</td><td></td><td></td></tr>
+          <tr><td>musician3</td><td></td><td></td></tr>
+          <tr><td>musician4</td><td></td><td></td></tr>
+        </tbody>
+      </table>
+      <p class="csv-format-note">Rows where the tune name is not found are skipped with a warning in the results.</p>
+    </details>
+    <div id="refs-csv-upload-area">
+      <input type="file" id="refs-csv-file-input" accept=".csv,.tsv,text/csv" />
+    </div>
+    <div id="refs-csv-results" hidden></div>
+    <div class="modal-actions">
+      <button id="btn-refs-csv-import" disabled>Import</button>
+      <button id="btn-refs-csv-cancel">Cancel</button>
+    </div>
+  </dialog>
+
   <!-- Tooltip for truncated mobile text -->
   <div id="mob-tooltip" hidden></div>