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/Accounts/Edit.cshtml

@@ -1,10 +1,10 @@
-@model PowderCoating.Application.DTOs.Accounting.EditAccountDto
+@model PowderCoating.Application.DTOs.Accounting.EditAccountDto
 
 @{
     ViewData["Title"] = "Edit Account";
     ViewData["PageIcon"] = "bi-pencil-square";
     ViewData["PageHelpTitle"] = "Edit Account";
-    ViewData["PageHelpContent"] = "You can change number, name, type, sub-type, parent, and opening balance. Changing the account type or sub-type on an account that already has transactions is allowed but use caution — it changes how balances are reported going forward. Inactive accounts are hidden from pickers but preserved in history.";
+    ViewData["PageHelpContent"] = "You can change number, name, type, sub-type, parent, and opening balance. Changing the account type or sub-type on an account that already has transactions is allowed but use caution — it changes how balances are reported going forward. Inactive accounts are hidden from pickers but preserved in history.";
 }
 
 <div class="d-flex justify-content-start mb-4">
@@ -18,7 +18,7 @@
                 <form asp-action="Edit" method="post">
                     @Html.AntiForgeryToken()
                     <input asp-for="Id" type="hidden" />
-                    <div asp-validation-summary="ModelOnly" class="alert alert-danger mb-3"></div>
+                    <div asp-validation-summary="ModelOnly" class="alert alert-danger alert-permanent mb-3"></div>
 
                     <div class="row g-3">
                         <div class="col-sm-4">
@@ -27,7 +27,7 @@
                                 <a tabindex="0" class="help-icon" role="button"
                                    data-bs-toggle="popover" data-bs-placement="right" data-bs-trigger="focus"
                                    data-bs-title="Account Number"
-                                   data-bs-content="A numeric code for sorting and organizing accounts. Convention: 1000–1999 Assets, 2000–2999 Liabilities, 3000–3999 Equity, 4000–4999 Revenue, 5000–5999 Cost of Goods, 6000–9999 Expenses. Must be unique.">
+                                   data-bs-content="A numeric code for sorting and organizing accounts. Convention: 1000–1999 Assets, 2000–2999 Liabilities, 3000–3999 Equity, 4000–4999 Revenue, 5000–5999 Cost of Goods, 6000–9999 Expenses. Must be unique.">
                                     <i class="bi bi-question-circle"></i>
                                 </a>
                             </div>
@@ -81,12 +81,12 @@
                                 <a tabindex="0" class="help-icon" role="button"
                                    data-bs-toggle="popover" data-bs-placement="right" data-bs-trigger="focus"
                                    data-bs-title="Parent Account"
-                                   data-bs-content="Nest this account under a parent to create a hierarchy — e.g. 'Powder Costs' under 'Cost of Goods Sold'. Sub-accounts roll up into their parent on financial reports. Most accounts work fine without a parent.">
+                                   data-bs-content="Nest this account under a parent to create a hierarchy — e.g. 'Powder Costs' under 'Cost of Goods Sold'. Sub-accounts roll up into their parent on financial reports. Most accounts work fine without a parent.">
                                     <i class="bi bi-question-circle"></i>
                                 </a>
                             </div>
                             <select asp-for="ParentAccountId" asp-items="ViewBag.ParentAccounts" class="form-select">
-                                <option value="">— None —</option>
+                                <option value="">— None —</option>
                             </select>
                         </div>