Merge agent and mode into one (#1689)

The concept of mode has been deprecated, there is now only the agent field in the config.

An agent can be cycled through as your primary agent with <tab> or you can spawn a subagent by @ mentioning it. if you include a description of when to use it, the primary agent will try to automatically use it

Full docs here: https://opencode.ai/docs/agents/

packages/sdk/stainless/stainless.yml

@@ -51,12 +51,12 @@ resources:
       logLevel: LogLevel
       provider: Provider
       model: Model
-      mode: Mode
+      agent: Agent
     methods:
       get: get /app
       init: post /app/init
       log: post /log
-      modes: get /mode
+      agents: get /agent
       providers: get /config/providers
 
   find:
@@ -99,6 +99,8 @@ resources:
       fileSource: FileSource
       symbolSource: SymbolSource
       toolPart: ToolPart
+      agentPart: AgentPart
+      agentPartInput: AgentPartInput
       stepStartPart: StepStartPart
       stepFinishPart: StepFinishPart
       snapshotPart: SnapshotPart