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>

languages/wc-tier-package-prices-de_CH_informal.po

@@ -3,7 +3,7 @@
 # This file is distributed under the GPL v2 or later.
 msgid ""
 msgstr ""
-"Project-Id-Version: WooCommerce Tier and Package Prices 1.1.5\n"
+"Project-Id-Version: WooCommerce Tier and Package Prices 1.1.6\n"
 "Report-Msgid-Bugs-To: https://src.bundespruefstelle.ch/wc-tier-package-prices\n"
 "POT-Creation-Date: 2025-12-21 00:00+0000\n"
 "PO-Revision-Date: 2025-12-21 00:00+0000\n"

languages/wc-tier-package-prices-de_DE.po

@@ -3,7 +3,7 @@
 # This file is distributed under the GPL v2 or later.
 msgid ""
 msgstr ""
-"Project-Id-Version: WooCommerce Tier and Package Prices 1.1.5\n"
+"Project-Id-Version: WooCommerce Tier and Package Prices 1.1.6\n"
 "Report-Msgid-Bugs-To: https://src.bundespruefstelle.ch/wc-tier-package-prices\n"
 "POT-Creation-Date: 2025-12-21 00:00+0000\n"
 "PO-Revision-Date: 2025-12-21 00:00+0000\n"

languages/wc-tier-package-prices-en_US.po

@@ -3,7 +3,7 @@
 # This file is distributed under the GPL v2 or later.
 msgid ""
 msgstr ""
-"Project-Id-Version: WooCommerce Tier and Package Prices 1.1.5\n"
+"Project-Id-Version: WooCommerce Tier and Package Prices 1.1.6\n"
 "Report-Msgid-Bugs-To: https://src.bundespruefstelle.ch/wc-tier-package-prices\n"
 "POT-Creation-Date: 2025-12-21 00:00+0000\n"
 "PO-Revision-Date: 2025-12-21 00:00+0000\n"

languages/wc-tier-package-prices.pot

@@ -2,7 +2,7 @@
 # This file is distributed under the GPL v2 or later.
 msgid ""
 msgstr ""
-"Project-Id-Version: WooCommerce Tier and Package Prices 1.1.5\n"
+"Project-Id-Version: WooCommerce Tier and Package Prices 1.1.6\n"
 "Report-Msgid-Bugs-To: https://src.bundespruefstelle.ch/wc-tier-package-prices\n"
 "POT-Creation-Date: 2025-12-21 00:00+0000\n"
 "MIME-Version: 1.0\n"