refactor(stall_watch): HerdrSource needs the herdr name, no fallback to the original (Issue #71)

Refs #71

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.agents/skills/lib_py/stall_watch.py

@@ -155,12 +155,12 @@ class HerdrError(Exception):
 class HerdrSource(object):
     """Every herdr and OS read the judgement needs, in one place."""
 
-    def __init__(self, target, agent, session=None, name=None):
+    def __init__(self, target, agent, session=None, *, name):
         self.target, self.session = target, session or None
         # `name` is the name herdr knows the agent by (#66), worked out once
         # by StallWatch (#71); the kind is read off the original name, whose
         # suffix a long name's hash replaces.
-        self.name = name or target
+        self.name = name
         self.agent = resolve_agent(agent, target)
         adapter = get_adapter(self.agent) if self.agent else None
         self.resident = tuple(adapter.resident_children) if adapter else ()