settings: split danger zone into delete originals / delete all activities

Move "Delete original files" out of the Storage card and into the
Danger zone as a first, less-destructive step (simple confirm, no
password needed). "Delete all activity data" and "Delete account"
follow below it, both still password-gated. Descriptions clarify
exactly what each action does and does not remove.

site/src/pages/settings/index.astro

@@ -31,17 +31,6 @@ import Base from '../../layouts/Base.astro';
           <span id="st-total" class="text-white tabular-nums"></span>
         </div>
       </div>
-      <!-- Delete originals -->
-      <div id="del-originals-area" class="mt-4 hidden">
-        <p class="text-xs text-zinc-500 mb-3">
-          Original files are kept for reprocessing. Once your activities look correct you can free this space — the extracted data is not affected.
-        </p>
-        <button id="del-originals-btn"
-          class="px-4 py-2 rounded-lg text-sm bg-zinc-800 hover:bg-amber-900 hover:text-amber-300 text-zinc-300 transition-colors">
-          Delete original files
-        </button>
-        <p id="del-originals-status" class="text-xs mt-2 hidden"></p>
-      </div>
     </section>
 
     <!-- Profile card -->
@@ -141,10 +130,21 @@ import Base from '../../layouts/Base.astro';
     <section class="rounded-xl bg-zinc-900 border border-red-900/40 p-5">
       <h2 class="text-sm font-semibold text-red-400/70 uppercase tracking-wider mb-4">Danger zone</h2>
 
-      <!-- Delete activities -->
+      <!-- Delete original files -->
       <div class="mb-5">
-        <p class="text-sm text-zinc-300 font-medium mb-1">Reset activity data</p>
+        <p class="text-sm text-zinc-300 font-medium mb-1">Delete original files</p>
-        <p class="text-xs text-zinc-500 mb-3">Wipes all extracted activities, edits, and photos. Your account is kept. Cannot be undone.</p>
+        <p class="text-xs text-zinc-500 mb-3">Removes the raw source files kept for reprocessing (originals/). Your extracted activities, edits, and photos are not affected.</p>
+        <button id="del-originals-btn"
+          class="px-4 py-2 rounded-lg text-sm bg-zinc-800 hover:bg-amber-900 hover:text-amber-300 text-zinc-400 transition-colors">
+          Delete original files
+        </button>
+        <p id="del-originals-status" class="text-xs mt-2 hidden"></p>
+      </div>
+
+      <!-- Delete all activity data -->
+      <div class="border-t border-zinc-800 pt-5 mb-5">
+        <p class="text-sm text-zinc-300 font-medium mb-1">Delete all activity data</p>
+        <p class="text-xs text-zinc-500 mb-3">Wipes all extracted activities, edits, and photos. Your account and original files are kept. Cannot be undone.</p>
         <button id="del-activities-btn"
           class="px-4 py-2 rounded-lg text-sm bg-zinc-800 hover:bg-red-900 hover:text-red-300 text-zinc-400 transition-colors">
           Delete all activities
@@ -218,10 +218,6 @@ import Base from '../../layouts/Base.astro';
         document.getElementById('st-strava-row')!.classList.remove('hidden');
       }
 
-      if (d.originals_mb > 0) {
-        document.getElementById('del-originals-area')!.classList.remove('hidden');
-      }
-
       loading.classList.add('hidden');
       content.classList.remove('hidden');
     } catch (e: any) {
@@ -240,7 +236,8 @@ import Base from '../../layouts/Base.astro';
       const d = await r.json();
       if (r.ok) {
         setStatus(statusEl, `Freed ${fmtMb(d.freed_mb)}.`, true);
-        btn.closest('div')!.querySelector('button')!.remove();
+        btn.disabled = true;
+        btn.textContent = 'Already deleted';
         loadStorage();
       } else {
         btn.disabled = false;