feat(web): implement Ship Dashboard with vitals and mobility sections

Adds NumericStepper and EnumDropdown UI components, VitalsSection (hull/armor/AC/con),
MobilitySection (speed/maneuver class/size), with debounced real-time updates.

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

web/src/index.css

@@ -298,3 +298,85 @@ button:disabled {
   opacity: 0.5;
   cursor: not-allowed;
 }
+
+/* Dashboard */
+.dashboard-section {
+  margin-bottom: var(--spacing-lg);
+}
+
+.section-title {
+  font-size: 0.9rem;
+  font-weight: 600;
+  text-transform: uppercase;
+  letter-spacing: 0.05em;
+  color: var(--color-text-muted);
+  margin-bottom: var(--spacing-sm);
+  border-bottom: 1px solid var(--color-border);
+  padding-bottom: var(--spacing-xs);
+}
+
+.stat-grid {
+  display: grid;
+  grid-template-columns: 1fr 1fr;
+  gap: var(--spacing-sm);
+}
+
+/* Stepper */
+.stepper {
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-xs);
+}
+
+.stepper-label {
+  font-size: 0.8rem;
+  color: var(--color-text-muted);
+}
+
+.stepper-controls {
+  display: flex;
+  align-items: center;
+  gap: var(--spacing-xs);
+}
+
+.stepper-btn {
+  width: 36px;
+  height: 36px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  background: var(--color-accent);
+  color: var(--color-text);
+  font-size: 1.2rem;
+  font-weight: bold;
+  border-radius: var(--radius);
+  padding: 0;
+}
+
+.stepper-btn:hover:not(:disabled) {
+  background: var(--color-surface-hover);
+}
+
+.stepper-value {
+  min-width: 40px;
+  text-align: center;
+  font-weight: 600;
+  font-size: 1.1rem;
+}
+
+/* Dropdown */
+.dropdown-field {
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-xs);
+}
+
+.dropdown-label {
+  font-size: 0.8rem;
+  color: var(--color-text-muted);
+}
+
+.dropdown-select {
+  height: 36px;
+  padding: var(--spacing-xs) var(--spacing-sm);
+}