Button consistency sweep + mobile responsiveness patches

- Standardize modal dismiss/cancel buttons to btn-outline-secondary across 70+ views
- Remove btn-sm from page-level Create and Back buttons (Index + Detail pages)
- Fix Edit buttons on Details pages: btn-secondary -> btn-warning
- Fix form Cancel/Back links: btn-secondary -> btn-outline-secondary
- Add 10 CSS patches to site.css for mobile/tablet responsiveness:
  top-navbar overflow prevention, page-header flex-wrap at 575px,
  table action button min-height override, notification dropdown width cap,
  tablet content padding

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

src/PowderCoating.Web/Views/Jobs/Index.cshtml

@@ -455,7 +455,7 @@
                 </div>
             </div>
             <div class="modal-footer">
-                <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">Cancel</button>
+                <button type="button" class="btn btn-outline-secondary" data-bs-dismiss="modal">Cancel</button>
                 <button type="button" class="btn btn-primary" id="saveWorkerAssignment">
                     <i class="bi bi-save me-2"></i>Save Assignment
                 </button>
@@ -491,7 +491,7 @@
                 </div>
             </div>
             <div class="modal-footer">
-                <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">Cancel</button>
+                <button type="button" class="btn btn-outline-secondary" data-bs-dismiss="modal">Cancel</button>
                 <button type="button" class="btn btn-primary" id="savePriority">
                     <i class="bi bi-save me-2"></i>Save Priority
                 </button>
@@ -540,7 +540,7 @@
                 </div>
             </div>
             <div class="modal-footer">
-                <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">Cancel</button>
+                <button type="button" class="btn btn-outline-secondary" data-bs-dismiss="modal">Cancel</button>
                 <button type="button" class="btn btn-primary" id="saveStatus">
                     <i class="bi bi-save me-2"></i>Save Status
                 </button>