feat: Move to, Gitea context menu, Activity popover

Move to workspace:
- movePage() opens a dialog listing all workspaces via /api/workspaces
- doMove(wsId) calls PUT /api/pages/{id}/move with workspace_id
- Updated move API to accept JSON body with workspace_id for cross-workspace moves

Gitea workspace context menu:
- Right-click on any file/folder shows Rename + Delete options
- gwRename() prompts for new name, calls PUT /api/gitea/.../file
- gwDelete() confirms then calls DELETE /api/gitea/.../file
- Both trigger refreshTree() after success

Activity popover:
- 'Edited X ago' timestamp is now clickable (▾ indicator)
- Opens popover showing edited time + created date
- formatDate() helper for readable date formatting

app/templates/gitea_workspace.html

@@ -117,6 +117,7 @@
           <template x-for="item in sortedTreeItems" :key="item.path">
             <div class="ws-tree-item"
                  @click="item.type==='folder' ? drillDown(item.path) : openFile(item.path, item.sha)"
+                 @contextmenu.prevent="openGwContext($event, item)"
                  style="display:flex;align-items:center;gap:8px;padding:6px 8px;border-radius:6px;cursor:pointer;">
               <span x-text="item.type==='folder' ? '📁' : '📄'" style="font-size:16px;"></span>
               <span x-text="item.name" style="flex:1;font-size:14px;" :style="{ fontWeight: item.type==='folder' ? '500' : '400' }"></span>
@@ -124,6 +125,16 @@
             </div>
           </template>
         </div>
+
+        <!-- Context menu -->
+        <div class="gw-context-menu"
+             x-show="gwCtx.visible"
+             :style="'left:' + gwCtx.x + 'px; top:' + gwCtx.y + 'px'"
+             @click.outside="gwCtx.visible = false"
+             style="display:none;position:fixed;background:var(--bg-secondary);border:1px solid var(--border-strong);border-radius:8px;box-shadow:0 8px 24px rgba(0,0,0,.4);z-index:1100;min-width:160px;padding:4px;">
+          <div class="ctx-item" @click="gwRename()">✏️ Rename</div>
+          <div class="ctx-item ctx-danger" @click="gwDelete()">🗑 Delete</div>
+        </div>
       </div>
 
       <!-- New file form -->
@@ -207,6 +218,8 @@ function giteaWorkspace() {
     treeLoading: false,
     folderStack: [],
     currentPath: '',
+    // Context menu
+    gwCtx: { visible: false, x: 0, y: 0, item: null },
 
     get sortedTreeItems() {
       return [...this.treeItems].sort(function(a, b) {
@@ -257,6 +270,43 @@ function giteaWorkspace() {
       this.loadMainTree('');
     },
 
+    openGwContext(ev, item) {
+      this.gwCtx = { visible: true, x: ev.clientX, y: ev.clientY, item: item };
+    },
+    gwRename() {
+      this.gwCtx.visible = false;
+      var item = this.gwCtx.item;
+      if (!item) return;
+      var newName = prompt('Rename:', item.name);
+      if (!newName || !newName.trim() || newName.trim() === item.name) return;
+      var self = this;
+      var oldPath = item.path;
+      var newPath = oldPath.replace(/[^/]+$/, newName.trim());
+      fetch('/api/gitea/projects/' + this.owner + '/' + this.repo + '/file', {
+        method: 'PUT',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({ path: oldPath, new_path: newPath, message: 'Rename ' + oldPath + ' to ' + newPath })
+      }).then(function(r){ return r.json(); })
+        .then(function(d){
+          if (d.status === 'ok') { self.refreshTree(); }
+          else { window.showToast('Rename failed', 'error'); }
+        })
+        .catch(function(){ window.showToast('Rename failed', 'error'); });
+    },
+    gwDelete() {
+      this.gwCtx.visible = false;
+      var item = this.gwCtx.item;
+      if (!item) return;
+      if (!confirm('Delete ' + item.name + '?')) return;
+      var self = this;
+      fetch('/api/gitea/projects/' + this.owner + '/' + this.repo + '/file?path=' + encodeURIComponent(item.path) + '&sha=' + (item.sha || '') + '&message=Delete ' + item.path, {
+        method: 'DELETE'
+      }).then(function(r){
+        if (r.ok) { self.refreshTree(); }
+        else { window.showToast('Delete failed', 'error'); }
+      }).catch(function(){ window.showToast('Delete failed', 'error'); });
+    },
+
     async loadSidebarTree() {
       try {
         var r = await fetch('/api/gitea/projects/' + this.owner + '/' + this.repo + '/tree');