feat: refresh Week capacity with atomic reflow (Closes #1266)

frontend/index.html

@@ -522,7 +522,7 @@
       <p class="small muted">See what is next and check each day’s load. Edit only when you are ready.</p>
       <p class="week-offline-snapshot" id="week-offline-snapshot" role="status" aria-live="polite" hidden></p>
       <button id="retry-week-live" type="button" hidden>Retry live Week Ahead</button>
-      <button id="open-week-capacity-import" type="button">Set capacity from calendar</button>
+      <button id="open-week-capacity-import" type="button">Refresh from calendar</button>
       <button id="open-week-availability" type="button">Set weekly availability</button>
       <section class="week-availability-editor" id="week-availability-editor" aria-labelledby="week-availability-title" hidden>
         <h3 id="week-availability-title">Weekly availability</h3>
@@ -565,9 +565,9 @@
       <button id="confirm-week-plan" type="button">Confirm Week Ahead</button>
     </section>
     <section class="week-capacity-import" id="week-capacity-import" aria-labelledby="week-capacity-title" hidden>
-      <header><div><div class="small">Private calendar import</div><h2 id="week-capacity-title">Set Week Ahead capacity</h2></div>
+      <header><div><div class="small">Private calendar refresh</div><h2 id="week-capacity-title">Refresh Week Ahead availability</h2></div>
         <button id="cancel-week-capacity-import" type="button">Cancel</button></header>
-      <p class="small muted">Your calendar is read only on this device. Event titles, people, locations, and the file are never saved or uploaded.</p>
+      <p class="small muted">Compare refreshed availability with planned load before anything changes. Your calendar is read only on this device; event titles, people, locations, and the file are never saved or uploaded.</p>
       <label>Calendar file
         <input id="week-capacity-file" type="file" accept=".ics,text/calendar" />
       </label>