Release version 1.1.6 - Critical fix for plugin activation

Fixed critical bug that prevented plugin activation in v1.1.3, v1.1.4, and v1.1.5.

Root Cause:
- WC_TPP_Cart and WC_TPP_Frontend classes were instantiated immediately when
  their files were loaded (via `new ClassName();` at bottom of files)
- This happened BEFORE WooCommerce was fully loaded
- Hook registration attempted to access WooCommerce functions before they existed
- Result: Fatal error during plugin activation

Solution:
- Removed immediate instantiation from class-wc-tpp-cart.php (line 251)
- Removed immediate instantiation from class-wc-tpp-frontend.php (line 186)
- Added init_classes() method to main plugin class
- Classes now instantiated via woocommerce_loaded hook
- Ensures WooCommerce is fully initialized before any hooks are registered

Changes:
- includes/class-wc-tpp-cart.php - Removed `new WC_TPP_Cart();`
- includes/class-wc-tpp-frontend.php - Removed `new WC_TPP_Frontend();`
- wc-tier-and-package-prices.php - Added init_classes() and woocommerce_loaded hook
- CHANGELOG.md - Added v1.1.6 section
- composer.json - Version 1.1.6
- All translation files updated to 1.1.6
- All .mo files recompiled

This fix ensures proper WordPress plugin lifecycle:
1. Plugin file loaded
2. Classes defined (but not instantiated)
3. WooCommerce loads
4. woocommerce_loaded hook fires
5. Classes instantiated with full WooCommerce availability

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

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

CHANGELOG.md

@@ -5,6 +5,19 @@ All notable changes to WooCommerce Tier and Package Prices will be documented in
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [1.1.6] - 2025-12-21
+
+### Fixed
+- **CRITICAL:** Plugin activation fatal error in v1.1.3, v1.1.4, and v1.1.5
+- Fatal error caused by premature class instantiation before WooCommerce is loaded
+- Removed immediate class instantiation from `class-wc-tpp-cart.php` and `class-wc-tpp-frontend.php`
+
+### Technical
+- Moved `WC_TPP_Cart` and `WC_TPP_Frontend` instantiation to `woocommerce_loaded` hook
+- Added `init_classes()` method to main plugin class for controlled class initialization
+- Ensures WooCommerce is fully loaded before registering hooks that depend on WC functions
+- Fixed hook registration timing to prevent accessing WooCommerce before it's available
+
 ## [1.1.5] - 2025-12-21
 
 ### Fixed