feat(web): implement weapons section with add/edit/detail modals and notes

Adds WeaponCard with inline ammo stepper and status dropdown, AddWeaponModal,
WeaponDetailModal with full editing, and debounced NotesSection.

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

web/src/index.css

@@ -380,3 +380,99 @@ button:disabled {
   height: 36px;
   padding: var(--spacing-xs) var(--spacing-sm);
 }
+
+/* Section header with inline button */
+.section-header {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  margin-bottom: var(--spacing-sm);
+  border-bottom: 1px solid var(--color-border);
+  padding-bottom: var(--spacing-xs);
+}
+
+.section-header .section-title {
+  border-bottom: none;
+  margin-bottom: 0;
+  padding-bottom: 0;
+}
+
+.btn-sm {
+  font-size: 0.8rem;
+  padding: var(--spacing-xs) var(--spacing-sm);
+}
+
+/* Weapons */
+.weapons-list {
+  display: flex;
+  flex-direction: column;
+  gap: var(--spacing-sm);
+}
+
+.weapon-card {
+  background: var(--color-surface);
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius);
+  padding: var(--spacing-sm) var(--spacing-md);
+  cursor: pointer;
+  transition: background-color 0.15s;
+}
+
+.weapon-card:hover {
+  background: var(--color-surface-hover);
+}
+
+.weapon-card-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  margin-bottom: var(--spacing-xs);
+}
+
+.weapon-card-name {
+  font-weight: 600;
+  font-size: 0.95rem;
+}
+
+.weapon-card-damage {
+  font-size: 0.85rem;
+  color: var(--color-primary);
+}
+
+.weapon-card-controls {
+  display: flex;
+  align-items: center;
+  gap: var(--spacing-md);
+}
+
+.weapon-ammo {
+  display: flex;
+  align-items: center;
+  gap: var(--spacing-xs);
+}
+
+.weapon-ammo-value {
+  font-size: 0.85rem;
+  min-width: 40px;
+  text-align: center;
+}
+
+.stepper-btn-sm {
+  width: 28px;
+  height: 28px;
+  font-size: 1rem;
+}
+
+.weapon-status-select {
+  width: auto;
+  font-size: 0.8rem;
+  height: 28px;
+  padding: 0 var(--spacing-sm);
+}
+
+/* Notes */
+.notes-textarea {
+  width: 100%;
+  min-height: 80px;
+  resize: vertical;
+}