feat(a11y): semantic colour system (#21 phase 1)

Replaces every hard-coded colour with semantic asset colours that adapt to
light, dark, and Increase Contrast. Dark mode stays locked, so this is a
pure refactor: the audit reports the same findings before and after.

The accent is now blue rather than cyan, per the tech/DNS theme.

Why custom values rather than the system palette: every system colour
fails WCAG AA in light mode. Measured on white — systemYellow 1.51:1,
systemOrange 2.20:1, systemGreen 2.22:1, systemCyan 2.54:1, systemRed
3.55:1. All of them pass in dark mode, which is why the dark-locked app
looked fine, and why unlocking light mode was never a matter of deleting
.preferredColorScheme(.dark). Every new value clears 4.5:1 as text on its
page, its card, and its own 16% badge tint — the way AppStatusBadgeView
actually draws it.

The accent needed splitting in two. As text on a dark background it must
be light; as a fill behind a white label it must be dark. #4DA3FF reads
8.00:1 as text on black but 2.63:1 behind white text, so StatusInfo /
AccentColor cover the foreground role and AccentFill covers
.borderedProminent. AppOnAccent is the label colour for a solid fill and
flips by scheme.

Colours live in Shared/Colors.xcassets rather than the app catalog: the
Shared folder is already a synchronized group in all three targets, so
the widget and share extension pick the palette up with no project-file
surgery. AccentColor stays in the app catalog as the global tint — and is
now actually defined, having been an empty colorset that silently left
system controls rendering in stock blue while custom chrome used cyan.

Two deliberate visual changes: orange folds into StatusWarning and pink
into StatusCritical. They encoded the same severity as the colours they
now share, and both sites also carry a text label.

Audit findings drop 15 to 14, and one of the originals turned out to be
a phantom: the Inspect contrast failure was the Run button in its
disabled state, which WCAG 1.4.3 exempts. testInspectScreen now types a
domain first so the audit measures an enabled control. Findings also
carry the offending element now, so the remaining clipped-text items name
themselves ("No Portfolio Yet", "Search domains") instead of being
anonymous.

1 files changed, 10 insertions, 10 deletions

diff --git a/DomainDig/BatchResultsView.swift b/DomainDig/BatchResultsView.swift
index 027d074..afef5cb 100644
--- a/DomainDig/BatchResultsView.swift
+++ b/DomainDig/BatchResultsView.swift
@@ -13,7 +13,7 @@ struct BatchResultsView: View {
                 if viewModel.batchLookupRunning {
                     VStack(alignment: .trailing, spacing: 4) {
                         ProgressView(value: Double(viewModel.batchCompletedCount), total: Double(max(viewModel.batchTotalCount, 1)))
-                            .tint(.cyan)
+                            .tint(Color(.statusInfo))
                             .frame(width: 120)
                         Text(viewModel.batchProgressLabel)
                             .font(appDensity.font(.caption2))
@@ -110,7 +110,7 @@ struct BatchResultRowView: View {
             if let errorMessage = result.errorMessage {
                 Text(errorMessage)
                     .font(appDensity.font(.caption2))
-                    .foregroundStyle(result.status == .failed ? .red : .secondary)
+                    .foregroundStyle(result.status == .failed ? Color(.statusCritical) : .secondary)
             }
         }
         .frame(maxWidth: .infinity, alignment: .leading)
@@ -138,29 +138,29 @@ struct BatchResultRowView: View {
             title: availabilityText,
             systemImage: "exclamationmark.circle",
             foregroundColor: .secondary,
-            backgroundColor: Color(.systemGray5).opacity(0.55)
+            backgroundColor: Color(.appSurfaceElevated)
         )
     }
 
     private var quickStatusBadge: AppStatusBadgeModel {
         switch result.status {
         case .pending:
-            return .init(title: "Pending", systemImage: "clock", foregroundColor: .secondary, backgroundColor: Color(.systemGray5).opacity(0.55))
+            return .init(title: "Pending", systemImage: "clock", foregroundColor: .secondary, backgroundColor: Color(.appSurfaceElevated))
         case .running:
-            return .init(title: "Running", systemImage: "arrow.clockwise", foregroundColor: .cyan, backgroundColor: .cyan.opacity(0.16))
+            return .init(title: "Running", systemImage: "arrow.clockwise", foregroundColor: Color(.statusInfo), backgroundColor: Color(.statusInfo).opacity(0.16))
         case .completed:
             if result.changeClassification == .critical || result.certificateWarningLevel == .critical || result.riskLevel == .high {
-                return .init(title: "Critical", systemImage: "exclamationmark.octagon.fill", foregroundColor: .red, backgroundColor: .red.opacity(0.16))
+                return .init(title: "Critical", systemImage: "exclamationmark.octagon.fill", foregroundColor: Color(.statusCritical), backgroundColor: Color(.statusCritical).opacity(0.16))
             }
             if result.changeClassification == .warning || result.changeSeverity == .medium || result.certificateWarningLevel == .warning {
-                return .init(title: "Warning", systemImage: "exclamationmark.triangle.fill", foregroundColor: .yellow, backgroundColor: .yellow.opacity(0.16))
+                return .init(title: "Warning", systemImage: "exclamationmark.triangle.fill", foregroundColor: Color(.statusWarning), backgroundColor: Color(.statusWarning).opacity(0.16))
             }
             if result.quickStatus == "Changed" {
-                return .init(title: "Changed", systemImage: "arrow.triangle.2.circlepath", foregroundColor: .cyan, backgroundColor: .cyan.opacity(0.16))
+                return .init(title: "Changed", systemImage: "arrow.triangle.2.circlepath", foregroundColor: Color(.statusInfo), backgroundColor: Color(.statusInfo).opacity(0.16))
             }
-            return .init(title: "Stable", systemImage: "checkmark.circle.fill", foregroundColor: .green, backgroundColor: .green.opacity(0.16))
+            return .init(title: "Stable", systemImage: "checkmark.circle.fill", foregroundColor: Color(.statusPositive), backgroundColor: Color(.statusPositive).opacity(0.16))
         case .failed:
-            return .init(title: "Failed", systemImage: "xmark.circle.fill", foregroundColor: .red, backgroundColor: .red.opacity(0.16))
+            return .init(title: "Failed", systemImage: "xmark.circle.fill", foregroundColor: Color(.statusCritical), backgroundColor: Color(.statusCritical).opacity(0.16))
         }
     }
 }