fix(acp): rename AuthMethod to AuthMethodAgent for agent-client-protocol 0.9.0

Straight rename to match the 0.9.0 API where AuthMethod was split into
AuthMethodAgent, AuthMethodEnvVar, AuthMethodTerminal. Bump pin to >=0.9.0,<1.0.

Co-authored-by: Mibayy <mibayy@users.noreply.github.com>

acp_adapter/server.py

@@ -12,7 +12,7 @@ import acp
 from acp.schema import (
     AgentCapabilities,
     AuthenticateResponse,
-    AuthMethod,
+    AuthMethodAgent,
     ClientCapabilities,
     EmbeddedResourceContentBlock,
     ForkSessionResponse,
@@ -177,7 +177,7 @@ class HermesACPAgent(acp.Agent):
         auth_methods = None
         if provider:
             auth_methods = [
-                AuthMethod(
+                AuthMethodAgent(
                     id=provider,
                     name=f"{provider} runtime credentials",
                     description=f"Authenticate Hermes using the currently configured {provider} runtime credentials.",