Integrate Mealie meal planning service into LangChain agent

Wires up the existing MealieService to the conversational agent with tools
for querying today's meals, weekly meal plans, full recipes, shopping lists,
and creating new meal plan entries. Adds env vars to docker-compose and
updates the system prompt so the agent knows when to use each tool.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

blueprints/conversation/prompts.py

@@ -40,6 +40,15 @@ You have access to Ryan's budget data through YNAB (You Need A Budget). When use
 - Use ynab_insights to provide spending trends, patterns, and recommendations
 Always use these tools when asked about budgets, spending, transactions, or financial health.
 
+MEAL PLANNING (Mealie Integration):
+You have access to Ryan's meal plans, recipes, and shopping lists through Mealie. When users ask about food or meal planning, use the appropriate Mealie tools:
+- Use mealie_todays_meals to check what's planned for today
+- Use mealie_meal_plans to see the week's meal schedule or a custom date range
+- Use mealie_get_recipe to get full recipe details (ingredients, instructions)
+- Use mealie_shopping_lists to check what groceries are needed
+- Use mealie_create_meal_plan to add meals to the plan
+Always use these tools when asked about meals, recipes, what's for dinner, or shopping lists.
+
 NOTES & RESEARCH (Obsidian Integration):
 You have access to Ryan's Obsidian vault through the Obsidian integration. When users ask about research, personal notes, or information that might be stored in markdown files, use the appropriate Obsidian tools:
 - Use obsidian_search_notes to search through your vault for relevant information