feat: Add Gemini AI integration for product title and description optimization

- Implemented Gemini API service for generating optimized product titles and descriptions based on Google Merchant Center guidelines.
- Added settings for Gemini API key and model selection in user settings.
- Enhanced product management views to support AI-generated suggestions for titles and descriptions.
- Enabled state saving for various data tables across campaign, terms, logs, and products views.
- Introduced AI prompt templates for generating product descriptions and categories.

templates/campaign_terms/main_view.php

@@ -1370,6 +1370,7 @@ function build_ad_groups_table( rows )
 
   terms_ad_groups_table = new DataTable( '#terms_ad_groups_table', {
     data: rows || [],
+    stateSave: true,
     processing: false,
     serverSide: false,
     autoWidth: false,
@@ -1421,6 +1422,7 @@ function build_search_terms_table( rows, negative_keywords )
 
   terms_search_table = new DataTable( '#terms_search_table', {
     data: rows || [],
+    stateSave: true,
     processing: false,
     serverSide: false,
     autoWidth: false,
@@ -1512,6 +1514,7 @@ function build_negative_terms_table( rows )
 
   terms_negative_table = new DataTable( '#terms_negative_table', {
     data: rows || [],
+    stateSave: true,
     processing: false,
     serverSide: false,
     autoWidth: false,
@@ -1586,6 +1589,7 @@ function build_keywords_table( rows )
 
   terms_keywords_table = new DataTable( '#terms_keywords_table', {
     data: rows || [],
+    stateSave: true,
     processing: false,
     serverSide: false,
     autoWidth: false,