Release version 1.2.8 - Currency display and data deletion fixes

Fixed two important bugs reported in v1.2.7:

Bug 1: Currency Symbol Missing in Admin Headers and Placeholders
- Table headers now show "Price (CURRENCY)" instead of just "Price"
- Input placeholders include currency symbol (e.g., "9.99 $")
- Better UX for multi-currency stores

Bug 2: Variation Pricing Data Not Deleted Properly (Critical)
- Empty pricing arrays were being saved instead of deleted
- Fixed save logic to check if arrays are empty after filtering
- Properly deletes post meta when all entries are removed
- Affects simple products, variable parents, and variations

Technical changes:
- Updated all table headers with currency symbol display
- Modified all render methods to pass currency_symbol to templates
- Updated Twig templates to use currency in placeholders
- Fixed save_tier_package_fields() and save_variation_pricing_fields()
- Added !empty() checks before update_post_meta() calls

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

composer.json

@@ -1,7 +1,7 @@
 {
     "name": "magdev/wc-tier-package-prices",
     "description": "WooCommerce plugin for tier pricing and package prices with Twig templates",
-    "version": "1.2.7",
+    "version": "1.2.8",
     "type": "wordpress-plugin",
     "license": "GPL-2.0-or-later",
     "authors": [