Design consistency audit fixes: alerts, cards, dark mode, utilities

Alert sweep (113 alerts, 79 files):
  All persistent static banners now carry alert-permanent so the
  layout's 5-second auto-dismiss cannot swallow guidance, warnings,
  or validation errors. Transient dismissible toasts left untouched.

CSS fixes (site.css):
  .card.shadow-sm      — strips rogue border from ~40 drifted cards
  .card-header.bg-white — rebinds to var(--bs-body-bg) so card
                          headers follow dark/light theme correctly
  Typography utilities  — .text-2xs (.68rem), .text-xs (.73rem)
  Token color classes   — .text-ember, .text-ok, .text-bad,
                          .text-warn, .text-cool, .bg-paper-2
  Layout utilities      — .mw-xs/sm/md/lg replace inline max-width
  Comment              — documents text-ember vs text-primary intent

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

src/PowderCoating.Web/Views/JobTemplates/Edit.cshtml

@@ -1,4 +1,4 @@
-@model PowderCoating.Core.Entities.JobTemplate
+@model PowderCoating.Core.Entities.JobTemplate
 @{
     ViewData["Title"] = $"Edit Template: {Model.Name}";
     ViewData["PageIcon"] = "bi-pencil-square";
@@ -31,7 +31,7 @@
                     <div class="mb-3">
                         <label class="form-label fw-semibold">Default Customer</label>
                         <select name="customerId" class="form-select">
-                            <option value="">— Any customer —</option>
+                            <option value="">— Any customer —</option>
                             @foreach (SelectListItem item in (ViewBag.Customers as IEnumerable<SelectListItem> ?? Enumerable.Empty<SelectListItem>()))
                             {
                                 if (item.Selected)
@@ -70,7 +70,7 @@
             </div>
         </div>
 
-        <div class="alert alert-info mt-3">
+        <div class="alert alert-info alert-permanent mt-3">
             <i class="bi bi-info-circle me-2"></i>
             To update the <strong>items and coatings</strong> on this template, create a new job with the desired configuration and save it as a template.
         </div>