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/Expenses/Details.cshtml

@@ -4,7 +4,7 @@
     ViewData["Title"] = $"Expense {Model.ExpenseNumber}";
     ViewData["PageIcon"] = "bi-receipt";
     ViewData["PageHelpTitle"] = "Expense";
-    ViewData["PageHelpContent"] = "A direct purchase paid at the time of transaction. Expense Account shows what was bought; Paid From shows which bank/cash account was debited. Edit to correct any details. Delete permanently removes the record — there is no Void for expenses.";
+    ViewData["PageHelpContent"] = "A direct purchase paid at the time of transaction. Expense Account shows what was bought; Paid From shows which bank/cash account was debited. Edit to correct any details. Delete permanently removes the record — there is no Void for expenses.";
 }
 
 <div class="d-flex justify-content-between align-items-center mb-4">
@@ -170,7 +170,7 @@
             <div class="modal-content">
                 <div class="modal-header">
                     <h5 class="modal-title" id="receiptModalLabel">
-                        <i class="bi bi-receipt me-2"></i>Receipt — @Model.ExpenseNumber
+                        <i class="bi bi-receipt me-2"></i>Receipt &mdash; @Model.ExpenseNumber
                     </h5>
                     <button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="Close"></button>
                 </div>