feat: add support for A1111 metadata schema

https://github.com/AUTOMATIC1111/stable-diffusion-webui/blob/cf2772fab0af5573da775e7437e6acdca424f26e/modules/processing.py#L672

modules/flags.py

@@ -32,6 +32,11 @@ default_parameters = {
     cn_ip: (0.5, 0.6), cn_ip_face: (0.9, 0.75), cn_canny: (0.5, 1.0), cn_cpds: (0.5, 1.0)
 }  # stop, weight
 
+metadata_schema =[
+    ('Fooocus (json)', 'fooocus'),
+    ('A1111 (plain text)', 'a1111'),
+]
+
 inpaint_engine_versions = ['None', 'v1', 'v2.5', 'v2.6']
 performance_selections = ['Speed', 'Quality', 'Extreme Speed']