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/CreditMemos/Create.cshtml

@@ -7,7 +7,7 @@
 
 <div class="d-flex justify-content-between align-items-center mb-3">
     <h4 class="mb-0"><i class="bi bi-journal-minus me-2 text-primary"></i>Issue Credit Memo</h4>
-    <a asp-action="Index" class="btn btn-outline-secondary btn-sm">
+    <a asp-action="Index" class="btn btn-outline-secondary">
         <i class="bi bi-arrow-left me-1"></i>Back to Credit Memos
     </a>
 </div>

src/PowderCoating.Web/Views/CreditMemos/Details.cshtml

@@ -59,7 +59,7 @@
                 <i class="bi bi-x-circle me-1"></i>Void
             </button>
         }
-        <a asp-action="Index" class="btn btn-outline-secondary btn-sm">
+        <a asp-action="Index" class="btn btn-outline-secondary">
             <i class="bi bi-arrow-left me-1"></i>Back
         </a>
     </div>
@@ -247,14 +247,14 @@
                     @if (openInvoices.Any())
                     {
                         <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="submit" class="btn btn-primary">Apply Credit</button>
                         </div>
                     }
                     else
                     {
                         <div class="modal-footer">
-                            <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">Close</button>
+                            <button type="button" class="btn btn-outline-secondary" data-bs-dismiss="modal">Close</button>
                         </div>
                     }
                 </form>
@@ -293,7 +293,7 @@
                         }
                     </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="submit" class="btn btn-danger">Void Credit Memo</button>
                     </div>
                 </form>

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

@@ -10,7 +10,7 @@
 
 <div class="d-flex justify-content-between align-items-center mb-3">
     <h4 class="mb-0"><i class="bi bi-journal-minus me-2 text-primary"></i>Credit Memos</h4>
-    <a asp-action="Create" class="btn btn-primary btn-sm">
+    <a asp-action="Create" class="btn btn-primary">
         <i class="bi bi-plus-lg me-1"></i>Issue Credit Memo
     </a>
 </div>