style(frontend) : apply UI corrections from design review

- Page titles in blue primary (#222783)
- Double main content margins (px-16 py-24)
- Remove blue border above sidebar timer
- Remove project color dot, use project color on title text
- All delete buttons/icons orange (#E2953C)
- Fix collapsed sidebar logo (object-cover object-left)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/components/time-tracking/TimeEntryList.vue

@@ -55,7 +55,7 @@
 
             <!-- Delete action -->
             <button
-                class="shrink-0 rounded-md p-1.5 text-neutral-300 opacity-0 transition hover:bg-red-50 hover:text-red-500 group-hover:opacity-100"
+                class="shrink-0 rounded-md p-1.5 text-neutral-300 opacity-0 transition hover:bg-orange-50 hover:text-[#E2953C] group-hover:opacity-100"
                 title="Supprimer"
                 @click.stop="emit('deleteEntry', entry)"
             >