Sweep all .cshtml files for encoding corruption; add pre-commit guard

Replace all corruption variants with HTML entities across 226 view files:
- 3-char UTF-8-as-Win1252 sequences (ae-corruption)
- Standalone smart/curly quotes that break C# Razor expressions
- Partially re-corrupted variants where the 3rd byte was normalised to ASCII

tools/Fix-Encoding.ps1: re-runnable sweep; uses [char] code points so the
script itself never contains a literal non-ASCII character; supports -DryRun

.githooks/pre-commit: blocks commits containing the ae-corruption byte
signature (xc3xa2xe2x82xac); git core.hooksPath = .githooks so the
hook is repo-committed and active for all future work on this machine.

Build clean; 225 unit tests pass.

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

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

@@ -125,7 +125,7 @@
         <div class="row g-2 align-items-end">
             <div class="col-md-3">
                 <input type="text" name="searchTerm" value="@searchTerm" class="form-control form-control-sm"
-                       placeholder="Search PO#, vendor, notes…" />
+                       placeholder="Search PO#, vendor, notes&hellip;" />
             </div>
             <div class="col-md-2">
                 <select name="statusFilter" class="form-select form-select-sm">
@@ -174,7 +174,7 @@
                                 <i class="bi bi-cart-check"></i>
                             </div>
                             <div class="mobile-card-title">
-                                <h6>@po.PoNumber @(po.IsOverdue ? " — Overdue" : "")</h6>
+                                <h6>@po.PoNumber @(po.IsOverdue ? " &mdash; Overdue" : "")</h6>
                                 <small>@po.VendorName</small>
                             </div>
                         </div>
@@ -260,7 +260,7 @@
                                     </span>
                                 </td>
                                 <td>@po.OrderDate.ToString("MM/dd/yyyy")</td>
-                                <td>@(po.ExpectedDeliveryDate?.ToString("MM/dd/yyyy") ?? "—")</td>
+                                <td>@(po.ExpectedDeliveryDate?.ToString("MM/dd/yyyy") ?? "&mdash;")</td>
                                 <td class="text-center">@po.ItemCount</td>
                                 <td class="text-end fw-semibold">$@po.TotalAmount.ToString("N2")</td>
                                 <td class="text-end">