Add Google and Groq AI providers, enhance provider manager, and implement conversation and logging services

- Introduced `Groq_AI_Provider_Google` and `Groq_AI_Provider_Groq` classes for handling AI interactions with Google and Groq respectively.
- Enhanced `Groq_AI_Provider_Manager` to register and manage multiple AI providers.
- Implemented `Groq_AI_Conversation_Manager` for managing conversation IDs and context hashes.
- Added `Groq_AI_Generation_Logger` for logging AI generation events and managing log tables.
- Developed `Groq_AI_Prompt_Builder` for constructing prompts and processing AI responses.
- Established `Groq_AI_Settings_Manager` for managing plugin settings, including context fields and module configurations.

includes/Providers/class-groq-ai-provider-openai.php

@@ -0,0 +1,36 @@
+<?php
+
+class Groq_AI_Provider_OpenAI extends Groq_AI_Abstract_OpenAI_Provider {
+	public function get_key() {
+		return 'openai';
+	}
+
+	public function get_label() {
+		return __( 'OpenAI', 'groq-ai-product-text' );
+	}
+
+	public function get_default_model() {
+		return 'gpt-4o-mini';
+	}
+
+	public function get_available_models() {
+		return [
+			'gpt-4o',
+			'gpt-4o-mini',
+			'gpt-4.1-mini',
+			'gpt-3.5-turbo',
+		];
+	}
+
+	public function get_option_key() {
+		return 'openai_api_key';
+	}
+
+	protected function get_endpoint() {
+		return 'https://api.openai.com/v1/chat/completions';
+	}
+
+	protected function get_models_endpoint() {
+		return 'https://api.openai.com/v1/models';
+	}
+}