Update ToolHive reference docs for v0.3.2

Author: github-actions[bot]

static/api-specs/toolhive-api.yaml

@@ -734,6 +734,10 @@ components:
         debug:
           description: Debug indicates whether debug mode is enabled
           type: boolean
+        env_file_dir:
+          description: EnvFileDir is the directory path to load environment files
+            from
+          type: string
         env_vars:
           additionalProperties:
             type: string