fix: editor usability and visual polish from UI scan

- Rule name is now an inline text field at the top of the editor; the
  pencil/rename button and alert are gone (it was unclear what the edit
  button did). Names are sanitized on commit: trimmed, falling back to
  the kind's default when emptied
- Day-of-week toggles fill the full row width with equal cells and
  >= 44pt tap targets
- 'Add Rule' commit button sits on a bar-material bottom inset so form
  content no longer collides with it while scrolling (found via
  computer-use scan; verified clean in a follow-up scan)
- Tests: 95 passing — new specs for the inline rename flow, day-toggle
  geometry, and name sanitization; three tests now scroll to reach
  bottom-of-form controls, matching real user behavior
- Spec §6 updated for the editor changes

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

Severed/Views/Components/DayOfWeekPicker.swift

@@ -12,12 +12,11 @@ struct DayOfWeekPicker: View {
     @Binding var days: Set<Weekday>
 
     var body: some View {
-        HStack(spacing: 8) {
+        HStack(spacing: 0) {
             ForEach(Weekday.displayOrder, id: \.self) { day in
                 dayToggle(day)
             }
         }
-        .padding(.vertical, 4)
     }
 
     private func dayToggle(_ day: Weekday) -> some View {
@@ -31,13 +30,16 @@ struct DayOfWeekPicker: View {
         } label: {
             Text(day.shortLabel)
                 .font(.subheadline.weight(.semibold))
-                .foregroundStyle(isOn ? Color.white : .secondary)
-                .frame(maxWidth: .infinity)
-                .aspectRatio(1, contentMode: .fit)
+                .foregroundStyle(isOn ? Color.white : Color.secondary)
+                .frame(width: 38, height: 38)
                 .background(
                     isOn ? AnyShapeStyle(.tint) : AnyShapeStyle(Color(.tertiarySystemFill)),
                     in: Circle()
                 )
+                // Each cell takes an equal share of the row and at least a
+                // 44pt-tall hit area, so the whole strip is comfortably tappable.
+                .frame(maxWidth: .infinity, minHeight: 44)
+                .contentShape(Rectangle())
         }
         .buttonStyle(.borderless)
         .accessibilityIdentifier("dayToggle-\(day.rawValue)")