Generated the JSON contracts of providers, the runtime, and services at compile time (#1150)

app/Tests/Serialization/Fixtures/responses-request.json

@@ -0,0 +1 @@
+{"model":"responses-model","input":[{"content":"You answer briefly.","role":"developer"},{"content":[{"type":"input_text","text":"What does the picture show?"},{"type":"input_image","image_url":"data:image/png;base64,iVBORw0KGgo="}],"role":"user"},{"type":"function_call","id":"fc_1","call_id":"call_1","name":"web_search","arguments":"{\u0022query\u0022:\u0022weather\u0022}"},{"type":"function_call_output","call_id":"call_1","output":"It is sunny."}],"stream":true,"store":false,"tools":[{"type":"function","name":"web_search","description":"Search the web.","parameters":{"type":"object","properties":{"query":{"type":"string","description":"The search query."},"page":{"type":["integer","null"],"description":"The page, starting at 1."}},"required":["query","page"],"additionalProperties":false},"strict":true}],"temperature":0.5,"top_k":40,"seed":12345678901,"stop":["END",7],"reasoning":{"effort":"low","summary":""},"logprobs":false}