Add TCPA-compliant SMS consent tracking for prospect quotes

- Quote entity: ProspectSmsConsent (bool) + ProspectSmsConsentedAt (DateTime?) fields
- QuoteDtos: consent fields on Create/Update/Convert DTOs with TCPA guidance text
- Quote Create/Edit views: SMS consent checkbox shown when mobile number is entered
- Quote ConvertToCustomer view: staff must re-confirm consent carries over to customer record
- QuoteApproval: consent state exposed in ViewModel and ApprovalPage for transparency
- Consent timestamp cleared when prospect quote is linked to an existing customer
- Migration: AddProspectSmsConsent

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

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

@@ -52,10 +52,23 @@
                         </div>
                         <div class="col-md-6">
                             <label asp-for="ProspectPhone" class="form-label">Phone <span class="text-danger">*</span></label>
-                            <input asp-for="ProspectPhone" class="form-control" type="tel" />
+                            <input asp-for="ProspectPhone" class="form-control" type="tel" id="editProspectPhone" />
                             <span asp-validation-for="ProspectPhone" class="text-danger"></span>
                         </div>
                     </div>
+                    <div class="row mt-2" id="editProspectSmsConsentRow">
+                        <div class="col-12">
+                            <div class="form-check">
+                                <input asp-for="ProspectSmsConsent" class="form-check-input" id="ProspectSmsConsent" />
+                                <label class="form-check-label fw-semibold" for="ProspectSmsConsent">
+                                    Customer verbally agreed to receive SMS notifications
+                                </label>
+                            </div>
+                            <small class="text-muted">
+                                <i class="bi bi-shield-check me-1"></i>Only check if the customer explicitly consented to receive text messages (TCPA compliance).
+                            </small>
+                        </div>
+                    </div>
                     <div class="row mt-2">
                         <div class="col-md-6">
                             <label asp-for="ProspectAddress" class="form-label"></label>
@@ -683,8 +696,20 @@
             if (custEl) new TomSelect(custEl, { placeholder: '-- Select Customer --', openOnFocus: true, maxOptions: false,
                 onChange: function(value) { onQuoteCustomerChanged({ value: value }); }
             });
+            // Show/hide SMS consent row based on phone field value
+            const phoneEl = document.getElementById('editProspectPhone');
+            if (phoneEl) {
+                phoneEl.addEventListener('input', updateEditProspectSmsConsent);
+                updateEditProspectSmsConsent();
+            }
         });
 
+        function updateEditProspectSmsConsent() {
+            const phoneEl = document.getElementById('editProspectPhone');
+            const row = document.getElementById('editProspectSmsConsentRow');
+            if (phoneEl && row) row.style.display = phoneEl.value.trim() ? '' : 'none';
+        }
+
         function onQuoteCustomerChanged(select) {
             const meta = JSON.parse(document.getElementById('quoteMetaData').textContent);
             const optOutIds = new Set(meta.emailOptOutCustomerIds || []);