feat(ai): default to Claude Sonnet 4.6 / Haiku 4.5, refresh model list

Sets the default AI chat model to anthropic/claude-sonnet-4.6 and the
default text-generation (WYSIWYG writing) model to anthropic/claude-
haiku-4.5 across all three layers where defaults live: the backend
hydrateDefaults() fallback in AiConfigurationService, the frontend
createDefaults() in AiConfigurationForm, and the docblock example in
AiTextGenerationService.

Refreshes the DriverRegistryProvider suggested-model list to only
include recent models from Anthropic (Sonnet 4.6, Haiku 4.5, Opus
4.6), OpenAI (GPT-5.4, GPT-5.4 mini), Google (Gemini 3.1 Pro preview,
Gemini 3.1 Flash Lite preview) and Z.AI (GLM 5.1, GLM 4.7 Flash).
Drops GPT-4o, Claude 3.5, Gemini 1.5 and Llama 3.3.

The underlying config still accepts any OpenRouter model ID, so the
suggested list is purely a UX surface — existing companies with a
custom ai_chat_model retain their value untouched.

app/Services/AiConfigurationService.php

@@ -302,9 +302,9 @@ class AiConfigurationService
             'ai_api_key' => '',
             'ai_base_url' => '',
             'ai_chat_enabled' => 'NO',
-            'ai_chat_model' => 'openai/gpt-4o',
+            'ai_chat_model' => 'anthropic/claude-sonnet-4.6',
             'ai_text_generation_enabled' => 'NO',
-            'ai_text_generation_model' => 'openai/gpt-4o-mini',
+            'ai_text_generation_model' => 'anthropic/claude-haiku-4.5',
         ], $settings);
     }