Implement Phase 9 & reusable components; skip Phase 8 (emails)

Phase 8 (Emails) skipped: WooCommerce email rendering uses
wc_get_template_html() which bypasses the Twig pipeline entirely.
Email customization deferred to plugins or block email editor.

Phase 9 - Supplementary (7 templates):
- Brand description with thumbnail, taxonomy archive delegate
- Brands A-Z shortcode with alphabetical index navigation
- Single brand thumbnail shortcode
- REST API OAuth login and grant-access forms
- Back-in-stock notification form with email input

Reusable Components (6 templates):
- price: product price display with sale handling
- rating: star rating with Bootstrap Icons (filled/half/empty)
- address-card: billing/shipping address card with edit link
- status-badge: contextual order status badges
- quantity-input: +/- input group widget
- form-field: universal form field renderer (text/select/textarea/checkbox)

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

templates/components/quantity-input.html.twig

@@ -0,0 +1,52 @@
+{#
+ # Quantity Input Component (Bootstrap 5)
+ #
+ # Reusable quantity input with +/- buttons using Bootstrap input-group.
+ # Works with the quantity.js script for increment/decrement.
+ #
+ # Expected context:
+ #   input_name  - Input name attribute (default: 'quantity')
+ #   input_id    - Input id attribute (optional)
+ #   input_value - Current quantity value (default: 1)
+ #   min_value   - Minimum quantity (default: 1)
+ #   max_value   - Maximum quantity (default: '')
+ #   step        - Step increment (default: 1)
+ #   classes     - Additional CSS classes (optional)
+ #
+ # Usage:
+ #   {% include 'components/quantity-input.html.twig' with {
+ #       input_name: 'quantity',
+ #       input_value: 1,
+ #       min_value: 1,
+ #       max_value: product.get_max_purchase_quantity()
+ #   } %}
+ #
+ # @package WcBootstrap
+ # @since 0.1.0
+ #}
+
+{% set qty_name = input_name|default('quantity') %}
+{% set qty_id = input_id|default('quantity_' ~ random()) %}
+{% set qty_value = input_value|default(1) %}
+{% set qty_min = min_value|default(1) %}
+{% set qty_max = max_value|default('') %}
+{% set qty_step = step|default(1) %}
+
+<div class="quantity input-group input-group-sm {{ classes|default('') }}" style="max-width: 140px;">
+    <button type="button" class="btn btn-outline-secondary qty-minus" aria-label="{{ __('Decrease quantity') }}">
+        <i class="bi bi-dash" aria-hidden="true"></i>
+    </button>
+    <input type="number"
+           class="form-control text-center"
+           name="{{ qty_name|esc_attr }}"
+           id="{{ qty_id|esc_attr }}"
+           value="{{ qty_value|esc_attr }}"
+           min="{{ qty_min|esc_attr }}"
+           {% if qty_max %}max="{{ qty_max|esc_attr }}"{% endif %}
+           step="{{ qty_step|esc_attr }}"
+           inputmode="numeric"
+           aria-label="{{ __('Quantity') }}" />
+    <button type="button" class="btn btn-outline-secondary qty-plus" aria-label="{{ __('Increase quantity') }}">
+        <i class="bi bi-plus" aria-hidden="true"></i>
+    </button>
+</div>