fix: expose collaboration functions on window for inline onclick handlers

templates/document_edit.html

···
 
     // ── Invite ────────────────────────────────────────────────────────────────
 
-    async function generateInvite() {
+    window.generateInvite = async function generateInvite() {
         const modal = document.getElementById('invite-modal');
         const body = document.getElementById('invite-modal-body');
         if (!modal) return;
···
         }
     }
 
-    function copyInviteLink() {
+    window.copyInviteLink = function copyInviteLink() {
         const input = document.getElementById('invite-link-input');
         if (!input) return;
         navigator.clipboard.writeText(input.value).then(() => {
···
         });
     }
 
-    function closeInviteModal() {
+    window.closeInviteModal = function closeInviteModal() {
         const modal = document.getElementById('invite-modal');
         if (modal) modal.style.display = 'none';
     }
···
     const commentForm = document.getElementById('comment-form');
     const commentTextEl = document.getElementById('comment-text');
 
-    function openCommentForm() {
+    window.openCommentForm = function openCommentForm() {
         if (!commentBtn || !commentForm) return;
         const rect = commentBtn.getBoundingClientRect();
         commentForm.style.top = rect.bottom + window.scrollY + 4 + 'px';
···
         commentTextEl.focus();
     }
 
-    function closeCommentForm() {
+    window.closeCommentForm = function closeCommentForm() {
         if (commentForm) commentForm.style.display = 'none';
         if (commentBtn) commentBtn.style.display = 'none';
         activeCommentParagraphId = null;
     }
 
-    async function submitComment() {
+    window.submitComment = async function submitComment() {
         if (!activeCommentParagraphId) return;
         const text = commentTextEl.value.trim();
         if (!text) return;