feat: Add presence heartbeat for Matrix online status

- matrix-gateway: POST /internal/matrix/presence/online endpoint
- usePresenceHeartbeat hook with activity tracking
- Auto away after 5 min inactivity
- Offline on page close/visibility change
- Integrated in MatrixChatRoom component

services/pdp-service/models.py

@@ -0,0 +1,59 @@
+from pydantic import BaseModel, Field
+from typing import Literal, Optional, Dict, Any
+from enum import Enum
+
+# Import ActorIdentity from auth-service (or redefine)
+class ActorType(str, Enum):
+    HUMAN = "human"
+    AGENT = "agent"
+    SERVICE = "service"
+
+class ActorIdentity(BaseModel):
+    actor_id: str
+    actor_type: ActorType
+    microdao_ids: list[str] = []
+    roles: list[str] = []
+
+class Action(str, Enum):
+    READ = "read"
+    WRITE = "write"
+    MANAGE = "manage"
+    INVITE = "invite"
+    SEND_MESSAGE = "send_message"
+    EXEC_TOOL = "exec_tool"
+    VIEW_USAGE = "view_usage"
+    ADMIN = "admin"
+
+class ResourceType(str, Enum):
+    MICRODAO = "microdao"
+    CHANNEL = "channel"
+    MESSAGE = "message"
+    AGENT = "agent"
+    TOOL = "tool"
+    PROJECT = "project"
+    USAGE = "usage"
+
+class ResourceRef(BaseModel):
+    type: ResourceType
+    id: str
+    
+    class Config:
+        use_enum_values = True
+
+class PolicyRequest(BaseModel):
+    actor: ActorIdentity
+    action: Action
+    resource: ResourceRef
+    context: Optional[Dict[str, Any]] = Field(default_factory=dict, description="Additional context")
+
+class PolicyDecision(BaseModel):
+    effect: Literal["permit", "deny"]
+    reason: Optional[str] = None
+    obligations: Optional[Dict[str, Any]] = Field(default_factory=dict, description="Additional obligations")
+    
+    class Config:
+        use_enum_values = True
+
+
+
+