fix: Fix Box definition error in REPL UI

- Fix 'not enough values to unpack' error by using predefined ROUNDED box
- Simplify input handling to avoid prompt_toolkit complexity
- Keep the visual bordered input box design
- Bump version to 0.3.18

The UI now works without crashing on startup!

pkg/hanzo/pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "hanzo"
-version = "0.3.17"
+version = "0.3.18"
 description = "Hanzo AI - Complete AI Infrastructure Platform with CLI, Router, MCP, and Agent Runtime"
 authors = [
     {name = "Hanzo AI", email = "[email protected]"},

pkg/hanzo/src/hanzo/cli.py

@@ -26,7 +26,7 @@ from .utils.output import console
 from .interactive.repl import HanzoREPL
 
 # Version
-__version__ = "0.3.17"
+__version__ = "0.3.18"
 
 
 @click.group(invoke_without_command=True)

pkg/hanzo/src/hanzo/dev.py

@@ -678,12 +678,9 @@ class HanzoDevREPL:
             'prompt': '#666666',  # Gray prompt arrow
         })
         
-        # Custom light gray box for Rich panels
-        LIGHT_GRAY_BOX = Box(
-            "╭─╮\n"
-            "│ │\n" 
-            "╰─╯\n"
-        )
+        # Use a predefined box style that's similar to Claude
+        from rich.box import ROUNDED
+        LIGHT_GRAY_BOX = ROUNDED
         
         # Header
         console.print()
@@ -705,14 +702,12 @@ class HanzoDevREPL:
                 console.print("[dim white]│[/dim white] ", end="")
                 
                 try:
-                    # Use prompt_toolkit for input with Claude-like styling
+                    # Get input - using simple input() wrapped in executor for async
+                    # The visual box is drawn by console.print statements
                     user_input = await asyncio.get_event_loop().run_in_executor(
                         None,
-                        lambda: prompt(
-                            '› ',  # Using › instead of > for a more modern look
-                            style=claude_style,
-                            message=''
-                        )
+                        input,
+                        '› '  # Using › instead of > for a more modern look
                     )
                     
                     # Draw input box border (bottom)