feat(meal-planner): add add_recipe_to_meal_plan tool (v0.11.0)

New write tool using mpcreateByRecipeId endpoint (parameters verified
from JS-bundle). Returns raw response pending production verification;
structured output planned for v0.11.1.

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

src/mcp_familywall/server.py

@@ -2320,6 +2320,49 @@ def get_meal_plan(date_from: str, date_to: str) -> str:
     return json.dumps(result, ensure_ascii=False, indent=2)
 
 
+# ---------------------------------------------------------------------------
+# Tool: add_recipe_to_meal_plan
+# ---------------------------------------------------------------------------
+
+
+@mcp.tool()
+def add_recipe_to_meal_plan(
+    recipe_id: str,
+    date: str,
+    meal_type: str,
+) -> str:
+    """Add a recipe from the recipe box to the meal plan.
+
+    IMPORTANT: Ask the user for confirmation before calling this tool.
+
+    Args:
+        recipe_id: Recipe metaId from get_recipes
+            (e.g. ``"recipe/16282169_7932720"``).
+        date:      Target date in ISO format (e.g. ``"2026-04-20"``).
+        meal_type: Meal slot — one of ``"BREAKFAST"``, ``"LUNCH"``,
+            ``"SNACK"``, or ``"DINNER"``.
+
+    Returns:
+        JSON with the new dish entry on success, or an error message.
+    """
+    if meal_type not in ("BREAKFAST", "LUNCH", "SNACK", "DINNER"):
+        return "Error: meal_type must be one of 'BREAKFAST', 'LUNCH', 'SNACK', 'DINNER'."
+
+    params: dict[str, Any] = {
+        "recipeId": recipe_id,
+        "date": date,
+        "type": meal_type,
+    }
+
+    try:
+        data = _authenticated_call("mpcreateByRecipeId", params)
+    except RuntimeError as exc:
+        return f"Error: {exc}"
+
+    # Return raw response until the structure is verified in production.
+    return json.dumps(data, ensure_ascii=False, indent=2)
+
+
 # ---------------------------------------------------------------------------
 # Factory
 # ---------------------------------------------------------------------------