refactor: reorganize into monorepo with separate subprojects

Structure webber into three independent subprojects:
- webber-api/: FastAPI backend server with all agent code
- webber-cli/: Standalone CLI client (renamed from cli/ to webber_cli/)
- webber-sandbox/: Test project for functional testing

Key changes:
- Each subproject has its own .venv (Python 3.12+)
- Added sandbox.sh for managing test project templates
- Created sandbox-templates/ with calculator-cli and empty starter
- Updated CI/CD for prefixed tags (api/v*, cli/v*)
- Added comprehensive AGENTS.md with operational instructions
- Added gitignore filtering to glob and grep tools
- Created pyproject.toml for each subproject

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

webber-api/src/cli/session/loop.py

@@ -0,0 +1,104 @@
+"""
+Agentic conversation loop for interactive CLI.
+"""
+from typing import Any
+
+from rich.console import Console
+
+from src.cli.session.context import SessionState
+from src.cli.ui.display import format_response
+from src.domains.agents.base import BaseAgent
+from src.shared.logging import logged, trace_span, get_logger
+
+logger = get_logger(__name__)
+
+
+class AgenticLoop:
+    """
+    Main conversation loop for interactive CLI sessions.
+
+    Manages state, executes agent turns, and handles display.
+    """
+
+    def __init__(
+        self,
+        agent: BaseAgent,
+        console: Console,
+        working_dir: str,
+    ):
+        """
+        Initialize the agentic loop.
+
+        Args:
+            agent: The agent to use for responses
+            console: Rich console for output
+            working_dir: Working directory for exploration
+        """
+        self.agent = agent
+        self.console = console
+        self.state = SessionState(working_dir=working_dir)
+
+    @logged()
+    async def run_turn(self, user_input: str) -> str:
+        """
+        Execute a single conversation turn.
+
+        Args:
+            user_input: User's prompt/question
+
+        Returns:
+            Agent's response
+        """
+        # Record user message
+        self.state.add_message("user", user_input)
+
+        async with trace_span("agentic_turn"):
+            try:
+                # Run the agent
+                response = await self.agent.run(
+                    user_input,
+                    working_dir=self.state.working_dir,
+                )
+
+                # Record assistant response
+                self.state.add_message("assistant", response)
+
+                return response
+
+            except Exception as e:
+                logger.exception(f"Agent error: {e}")
+                error_msg = f"Error: {e}"
+                self.state.add_message("assistant", error_msg)
+                raise
+
+    def display_response(self, response: str) -> None:
+        """Display agent response with formatting."""
+        formatted = format_response(response)
+        self.console.print(formatted)
+
+    def display_welcome(self) -> None:
+        """Display welcome message."""
+        from src.shared.config import get_settings
+        settings = get_settings()
+
+        self.console.print()
+        self.console.print(f"[title]{settings.app_name}[/] [dim]v{settings.app_version}[/]")
+        self.console.print(f"[dim]Working in:[/] [path]{self.state.working_dir}[/]")
+        self.console.print(f"[dim]Agent:[/] {self.agent.name} - {self.agent.description}")
+        self.console.print()
+        self.console.print("[dim]Type 'exit' or Ctrl+C to quit. Type 'clear' to reset history.[/]")
+        self.console.print()
+
+    def display_status(self) -> None:
+        """Display session status."""
+        self.console.print(f"[dim]Messages: {self.state.message_count} | Tokens: ~{self.state.estimated_tokens}[/]")
+
+    @property
+    def working_dir(self) -> str:
+        """Get current working directory."""
+        return self.state.working_dir
+
+    def set_working_dir(self, path: str) -> None:
+        """Change working directory."""
+        self.state.working_dir = path
+        self.console.print(f"[info]Changed directory to:[/] [path]{path}[/]")