refactor(agents,core,frontends): typed kinds, prompts per kind, frontend agents as parameters

tests/test_claude_sdk_backend.py

@@ -24,7 +24,7 @@ from claude_agent_sdk import (
 )
 
 from beaver_gateway.agents.base import ExposedMcp
-from beaver_gateway.agents.claude import ClaudeAgent, ClaudeOptions
+from beaver_gateway.agents.claude import ClaudeAgent, ClaudeOptions, Prompts
 from beaver_gateway.backends.claude_sdk import (
     ClaudeSdkBackend,
     RunnerConfig,
@@ -369,7 +369,7 @@ async def test_prompt_sources_are_assembled(cwd: Path) -> None:
     backend = _backend(
         cwd,
         InMemorySessionStore(),
-        prompt_sources=(("role", cwd / "a.md"), cwd / "b.md"),
+        prompts=Prompts(deep=(("role", cwd / "a.md"), cwd / "b.md")),
     )
     await _drain(
         backend.complete(

tests/test_conversations.py

@@ -634,3 +634,24 @@ async def test_spawn_defaults_agent_and_materializes(world: World) -> None:
     with pytest.raises(ValueError, match="no default agent for kind 'job'"):
         await world.conversations.spawn(kind="job", seed="clean")
     await world.settle(deep, 1)
+
+
+def test_agent_kinds_follow_prompts(tmp_path: Path) -> None:
+    from beaver_gateway.agents.claude import Prompts
+
+    plain = ClaudeAgent(name="p", model="m", system_prompt="hi", cwd=tmp_path)
+    assert plain.kinds == ("deep",)
+    dispatcher = ClaudeAgent(
+        name="x", model="m", cwd=tmp_path, prompts=Prompts(master=("a.md",), fork=())
+    )
+    assert dispatcher.kinds == ("master", "fork")
+    assert dispatcher.prompt_for("master") == ("a.md",)
+    assert dispatcher.prompt_for("deep") is None
+    with pytest.raises(ValueError, match=r"serves \['deep'\] without a prompt"):
+        ClaudeAgent(
+            name="y",
+            model="m",
+            cwd=tmp_path,
+            kinds=("master", "deep"),
+            prompts=Prompts(master=()),
+        )

tests/test_routing.py

@@ -23,7 +23,7 @@ class Stack:
     def __init__(self, world: World) -> None:
         self.world = world
         self.vault = world.root / "vault"
-        self.api = ApiFrontend(default_agents={"master": "a"})
+        self.api = ApiFrontend(master_agent="a")
         self.markdown = MarkdownFrontend(vault_path=self.vault, default_agent="d")
         self.anthropic = AnthropicMessagesFrontend()
         frontends = [self.api, self.anthropic, self.markdown]