feat: add configurable client tools and photo input

backend/services/tool_policy.py

@@ -0,0 +1,45 @@
+"""Runtime behavior shared by HTTP, MCP, and client tools.
+
+The stored definitions are intentionally plain dictionaries.  Keeping policy
+normalization here gives old definitions stable defaults without spreading
+fallback rules across PromptBrain, WorkflowBrain, and the pipeline.
+"""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+
+from models import RuntimeTool
+
+
+@dataclass(frozen=True)
+class ToolRuntimePolicy:
+    """Normalized interaction policy for one reusable tool."""
+
+    allow_interruptions: bool
+    execution_mode: str
+    wait_for_response: bool
+
+    @property
+    def cancel_on_interruption(self) -> bool:
+        """Pipecat uses this flag to distinguish waiting from async tools."""
+        return self.execution_mode == "immediate"
+
+    @property
+    def runs_llm_after_result(self) -> bool:
+        """Late async results update context without starting another reply."""
+        return self.execution_mode == "immediate"
+
+
+def policy_for_tool(tool: RuntimeTool) -> ToolRuntimePolicy:
+    """Read policy with backwards-compatible defaults per tool kind."""
+    config = (tool.definition or {}).get("config") or {}
+    default_mode = "async" if tool.type == "client" else "immediate"
+    mode = str(config.get("execution_mode") or default_mode)
+    if mode not in {"immediate", "async"}:
+        mode = default_mode
+    return ToolRuntimePolicy(
+        allow_interruptions=bool(config.get("allow_interruptions", True)),
+        execution_mode=mode,
+        wait_for_response=bool(config.get("wait_for_response", True)),
+    )