Key `TIPCAddress` instances by actor UUID

TIPC service names span the cluster while PIDs remain host-local.
Hashing only `(name, pid)` could therefore make same-named actors
on different hosts silently share one round-robin service name.

Derive the live-runtime seed from `Aid.uid` so the actor UUID
separates those names while keeping each identity reproducible.
Pin both properties with a deterministic regression test.

Review: PR #493 (copilot-pull-request-reviewer[bot],goodboy)
https://github.com/goodboy/tractor/pull/493

(this patch was generated in some part by `opencode` using
`gpt-5.6-sol` (`openai`))

tests/ipc/test_tipc.py

@@ -232,6 +232,43 @@ def test_get_random_collision_resistance():
     assert all(addr.is_valid for addr in addrs)
 
 
+def test_get_random_keys_live_actors_by_uuid(
+    monkeypatch: pytest.MonkeyPatch,
+):
+    '''
+    TIPC names are cluster-wide while PIDs are host-local. Hashing
+    only `(actor name, pid)` therefore made same-named actors with
+    equal PIDs on different hosts publish one service name, where
+    TIPC silently round-robins connects between them.
+
+    Hold the actor name and PID fixed while changing only its UUID;
+    distinct instances prove the globally unique identity field is
+    now part of the derivation.
+
+    '''
+    monkeypatch.setattr(_tipc.os, 'getpid', lambda: 1616)
+
+    def get_addr(uuid: str) -> TIPCAddress:
+        actor = SimpleNamespace(
+            aid=Aid(
+                name='worker',
+                uuid=uuid,
+                pid=1616,
+            )
+        )
+        monkeypatch.setattr(
+            _tipc,
+            'current_actor',
+            lambda **kwargs: actor,
+        )
+        return TIPCAddress.get_random()
+
+    first: TIPCAddress = get_addr('actor-uuid-a')
+    second: TIPCAddress = get_addr('actor-uuid-b')
+    assert first._instance != second._instance
+    assert get_addr('actor-uuid-a')._instance == first._instance
+
+
 def test_get_random_honors_bindspace():
     addr: TIPCAddress = TIPCAddress.get_random(
         bindspace=TIPC_NODE_SCOPE,

tractor/ipc/_tipc.py

@@ -369,10 +369,11 @@ class TIPCAddress(
         between them (verified). I.e. a collision manifests as
         *silent crosstalk*, not an error.
 
-        So the instance is a `blake2b` digest of a per-call-unique
+        So the instance is a `blake2b` digest of the actor UUID, or
-        seed, giving a well-spread 32b value. Being a pure fn of the
+        a per-call token outside a live runtime, giving a well-spread
-        seed it is also *reproducible*, which the (follow-up)
+        32b value. Being a pure fn of the seed it is also
-        registrar-less discovery fast-path wants.
+        *reproducible*, which the (follow-up) registrar-less
+        discovery fast-path wants.
 
         NOTE the residual risk is birthday-bounded: ~1.2e-2 for 10k
         names sharing one `_stype`. See plan 01 §9 for the
@@ -384,7 +385,7 @@ class TIPCAddress(
             err_on_no_runtime=False,
         )
         if actor:
-            seed: str = f'{actor.aid.name}@{pid}'
+            seed: str = '.'.join(actor.aid.uid)
         else:
             if is_root_process():
                 prefix: str = 'no_runtime_root'