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/Vendors/Edit.cshtml

@@ -4,7 +4,7 @@
     ViewData["Title"] = "Edit Vendor";
     ViewData["PageIcon"] = "bi-truck";
     ViewData["PageHelpTitle"] = "Edit Vendor";
-    ViewData["PageHelpContent"] = "Update vendor details here. Changing Default Expense Account or Payment Terms will apply to new bills going forward — existing bills are not affected. Marking a vendor Inactive hides them from purchase order pickers but preserves all history.";
+    ViewData["PageHelpContent"] = "Update vendor details here. Changing Default Expense Account or Payment Terms will apply to new bills going forward — existing bills are not affected. Marking a vendor Inactive hides them from purchase order pickers but preserves all history.";
 }
 
 <div class="row justify-content-center">
@@ -146,7 +146,7 @@
                             <a tabindex="0" class="help-icon" role="button"
                                data-bs-toggle="popover" data-bs-placement="right" data-bs-trigger="focus"
                                data-bs-title="Business Information"
-                               data-bs-content="Account Number is your customer account number at the vendor — appears on POs and bills. Default Expense Account pre-fills the expense category on bills created from this vendor's POs. Payment Terms sets the bill due date (Net 30 = 30 days after receipt). Credit Limit is informational only.">
+                               data-bs-content="Account Number is your customer account number at the vendor &mdash; appears on POs and bills. Default Expense Account pre-fills the expense category on bills created from this vendor's POs. Payment Terms sets the bill due date (Net 30 = 30 days after receipt). Credit Limit is informational only.">
                                 <i class="bi bi-question-circle"></i>
                             </a>
                         </div>