QOL improvements for arcade chat (#27)

Includes these improvements:
- Up-arrow loads your previous message history in the session (if
available)
- Shows the target engine URL when the chat starts
- Shows the model name in the chat: e.g. `Assistant (gpt-4o-mini): `
- URLs are re-written as clickable markdown links in the chat output
- mypy cleanup

arcade/arcade/cli/main.py

@@ -1,4 +1,5 @@
 import os
+import readline
 import threading
 import uuid
 import webbrowser
@@ -12,11 +13,12 @@ from rich.markup import escape
 from rich.table import Table
 from rich.text import Text
 
-from arcade.cli.authn import check_existing_login, LocalAuthCallbackServer
+from arcade.cli.authn import LocalAuthCallbackServer, check_existing_login
 from arcade.cli.utils import (
     OrderCommands,
     create_cli_catalog,
     display_streamed_markdown,
+    markdownify_urls,
     validate_and_get_config,
 )
 from arcade.client import Arcade
@@ -150,13 +152,20 @@ def chat(
                 "bold magenta underline",
             ),
             "\n",
+            "\n",
+            "Chatting with Arcade Engine at " + config.engine_url,
         )
         console.print(chat_header)
 
         while True:
-            user_input = console.input(
-                f"\n[magenta][bold]User[/bold] {user_attribution}:[/magenta] "
-            )
+            console.print(f"\n[magenta][bold]User[/bold] {user_attribution}:[/magenta] ")
+
+            # Use input() instead of console.input() to leverage readline history
+            user_input = input()
+
+            # Add the input to history
+            readline.add_history(user_input)
+
             messages.append({"role": "user", "content": user_input})
 
             if stream:
@@ -169,8 +178,7 @@ def chat(
                     user=user_email,
                     stream=True,
                 )
-                role, message = display_streamed_markdown(stream_response)
-                messages.append({"role": role, "content": message})
+                role, message_content = display_streamed_markdown(stream_response, model)
             else:
                 response = client.chat.completions.create(  # type: ignore[call-overload]
                     model=model,
@@ -183,11 +191,14 @@ def chat(
                 role = response.choices[0].message.role
 
                 if role == "assistant":
-                    console.print("\n[bold blue]Assistant:[/bold blue] ", Markdown(message_content))
+                    message_content = markdownify_urls(message_content)
+                    console.print(
+                        f"\n[bold blue]Assistant ({model}):[/bold blue] ", Markdown(message_content)
+                    )
                 else:
                     console.print(f"\n[bold magenta]{role}:[/bold magenta] {message_content}")
 
-                messages.append({"role": role, "content": message_content})
+            messages.append({"role": role, "content": message_content})
 
     except KeyboardInterrupt:
         console.print("Chat stopped by user.", style="bold blue")

arcade/arcade/cli/utils.py

@@ -3,7 +3,6 @@ from typing import TYPE_CHECKING
 import typer
 from openai.resources.chat.completions import ChatCompletionChunk, Stream
 from rich.console import Console
-from rich.live import Live
 from rich.markdown import Markdown
 from typer.core import TyperGroup
 from typer.models import Context
@@ -55,10 +54,11 @@ def create_cli_catalog(
     return catalog
 
 
-def display_streamed_markdown(stream: Stream[ChatCompletionChunk]) -> tuple[str, str]:
+def display_streamed_markdown(stream: Stream[ChatCompletionChunk], model: str) -> tuple[str, str]:
     """
     Display the streamed markdown chunks as a single line.
     """
+    from rich.live import Live
 
     full_message = ""
     role = ""
@@ -69,12 +69,32 @@ def display_streamed_markdown(stream: Stream[ChatCompletionChunk]) -> tuple[str,
             if role == "":
                 role = choice.delta.role or ""
                 if role == "assistant":
-                    console.print("\n[bold blue]Assistant:[/bold blue] ")
+                    console.print(f"\n[bold blue]Assistant ({model}):[/bold blue] ")
             if chunk_message:
                 full_message += chunk_message
                 markdown_chunk = Markdown(full_message)
                 live.update(markdown_chunk)
-        return role, full_message
+
+        # Markdownify URLs in the final message if applicable
+        if role == "assistant":
+            full_message = markdownify_urls(full_message)
+            live.update(Markdown(full_message))
+
+    return role, full_message
+
+
+def markdownify_urls(message: str) -> str:
+    """
+    Convert URLs in the message to markdown links.
+    """
+    import re
+
+    # This regex will match URLs that are not already formatted as markdown links:
+    # [Link text](https://example.com)
+    url_pattern = r"(?<!\]\()https?://\S+"
+
+    # Wrap all URLs in the message with markdown links
+    return re.sub(url_pattern, r"[Link](\g<0>)", message)
 
 
 def validate_and_get_config(