fix: Auth column width and Volumes tooltip

- Increased .col-auth width from 4em to 5em to prevent truncation
- Changed Volumes tooltip to generic "hover for breakdown" since
  volume names are autodiscovered

.claude/JOURNAL.md

@@ -267,3 +267,6 @@ This journal tracks substantive work on documents, diagrams, and documentation c
 
 88. **Task - Column tooltips and Auth column**: Added explanatory tooltips to all column headers and authorization status column<br>
     **Result**: **Column Tooltips**: Added title attributes to all 9 column headers in activity.html explaining each column's purpose (User="JupyterHub username", Status="Server status: green=active, yellow=idle, red=offline", CPU="Current CPU usage of user container", etc.). **Auth Column**: Added new sortable column after User showing NativeAuthenticator authorization status. Backend queries `users_info` table for `is_authorized` field via SQLAlchemy text query with exception handling for non-NativeAuthenticator setups. Frontend displays green checkmark (fa-check) for authorized users, red X (fa-times) for unauthorized. Added `formatAuth()` function and `getSortValue()` handling for `is_authorized` sorting (authorized=1 > not authorized=0). Added `.col-auth` CSS class with 4em width. Updated docs/activity-tracking-methodology.md with Auth column in table columns section, added `is_authorized` to API response schema, noted that all column headers have tooltips
+
+89. **Task - Activity table column fixes**: Fixed Auth column width and Volumes tooltip<br>
+    **Result**: Increased `.col-auth` width from 4em to 5em to prevent "Au..." truncation (now matches Status column width). Changed Volumes column tooltip from "Total size of user volumes (home, workspace, cache)" to "Total size of user volumes (hover for breakdown)" since volume names are autodiscovered and shown in cell tooltip

services/jupyterhub/html_templates_enhanced/activity.html

@@ -45,7 +45,7 @@
           <th class="col-status text-center sortable" data-sort="status" title="Server status: green=active, yellow=idle, red=offline">Status <span class="sort-icon"></span></th>
           <th class="col-cpu text-center sortable" data-sort="cpu_percent" title="Current CPU usage of user container">CPU <span class="sort-icon"></span></th>
           <th class="col-memory text-center sortable" data-sort="memory_mb" title="Current memory usage of user container">Memory <span class="sort-icon"></span></th>
-          <th class="col-volumes text-center sortable" data-sort="volume_size_mb" title="Total size of user volumes (home, workspace, cache)">Volumes <span class="sort-icon"></span></th>
+          <th class="col-volumes text-center sortable" data-sort="volume_size_mb" title="Total size of user volumes (hover for breakdown)">Volumes <span class="sort-icon"></span></th>
           <th class="col-timeleft text-center sortable" data-sort="time_remaining_seconds" title="Time until idle culler stops the server">Time Left <span class="sort-icon"></span></th>
           <th class="col-lastactive sortable" data-sort="last_activity" title="Time since last JupyterLab activity">Last Active <span class="sort-icon"></span></th>
           <th class="col-activity sortable" data-sort="activity_score" title="Activity score based on exponential decay (hover bar for %)">Activity <span class="sort-icon"></span></th>

services/jupyterhub/html_templates_enhanced/static/custom.css

@@ -1536,8 +1536,8 @@ textarea.form-control {
 }
 
 .activity-table .col-auth {
-  width: 4em;
-  min-width: 4em;
+  width: 5em;
+  min-width: 5em;
 }
 
 .activity-table .col-status {