Revert "Early 0.18 work (#22138)" (#22142)

This reverts commit d24b96d3bb.

frigate/api/defs/response/chat_response.py

@@ -1,37 +0,0 @@
-"""Chat API response models."""
-
-from typing import Any, Optional
-
-from pydantic import BaseModel, Field
-
-
-class ToolCall(BaseModel):
-    """A tool call from the LLM."""
-
-    id: str = Field(description="Unique identifier for this tool call")
-    name: str = Field(description="Tool name to call")
-    arguments: dict[str, Any] = Field(description="Arguments for the tool call")
-
-
-class ChatMessageResponse(BaseModel):
-    """A message in the chat response."""
-
-    role: str = Field(description="Message role")
-    content: Optional[str] = Field(
-        default=None, description="Message content (None if tool calls present)"
-    )
-    tool_calls: Optional[list[ToolCall]] = Field(
-        default=None, description="Tool calls if LLM wants to call tools"
-    )
-
-
-class ChatCompletionResponse(BaseModel):
-    """Response from chat completion."""
-
-    message: ChatMessageResponse = Field(description="The assistant's message")
-    finish_reason: str = Field(
-        description="Reason generation stopped: 'stop', 'tool_calls', 'length', 'error'"
-    )
-    tool_iterations: int = Field(
-        default=0, description="Number of tool call iterations performed"
-    )