feat: restore ACP server implementation from PR #949 (#1254)

Restore the ACP editor-integration implementation that was present on the
original PR branch but did not actually land in main.

Includes:
- acp_adapter/ server, session manager, event bridge, auth, permissions,
  and tool helpers
- hermes acp subcommand and hermes-acp entry point
- hermes-acp curated toolset
- ACP registry manifest, setup guide, and ACP test suite
- jupyter-live-kernel data science skill from the original branch

Also updates the revived ACP code for current main by:
- resolving runtime providers through the modern shared provider router
- binding ACP sessions to per-session cwd task overrides
- tracking duplicate same-name tool calls with FIFO IDs
- restoring terminal approval callbacks after prompts
- normalizing supporting docs/skill metadata

Validated with tests/acp and the full pytest suite (-n0).

tests/acp/test_auth.py

@@ -0,0 +1,56 @@
+"""Tests for acp_adapter.auth — provider detection."""
+
+from acp_adapter.auth import has_provider, detect_provider
+
+
+class TestHasProvider:
+    def test_has_provider_with_resolved_runtime(self, monkeypatch):
+        monkeypatch.setattr(
+            "hermes_cli.runtime_provider.resolve_runtime_provider",
+            lambda: {"provider": "openrouter", "api_key": "sk-or-test"},
+        )
+        assert has_provider() is True
+
+    def test_has_no_provider_when_runtime_has_no_key(self, monkeypatch):
+        monkeypatch.setattr(
+            "hermes_cli.runtime_provider.resolve_runtime_provider",
+            lambda: {"provider": "openrouter", "api_key": ""},
+        )
+        assert has_provider() is False
+
+    def test_has_no_provider_when_runtime_resolution_fails(self, monkeypatch):
+        def _boom():
+            raise RuntimeError("no provider")
+
+        monkeypatch.setattr("hermes_cli.runtime_provider.resolve_runtime_provider", _boom)
+        assert has_provider() is False
+
+
+class TestDetectProvider:
+    def test_detect_openrouter(self, monkeypatch):
+        monkeypatch.setattr(
+            "hermes_cli.runtime_provider.resolve_runtime_provider",
+            lambda: {"provider": "openrouter", "api_key": "sk-or-test"},
+        )
+        assert detect_provider() == "openrouter"
+
+    def test_detect_anthropic(self, monkeypatch):
+        monkeypatch.setattr(
+            "hermes_cli.runtime_provider.resolve_runtime_provider",
+            lambda: {"provider": "anthropic", "api_key": "sk-ant-test"},
+        )
+        assert detect_provider() == "anthropic"
+
+    def test_detect_none_when_no_key(self, monkeypatch):
+        monkeypatch.setattr(
+            "hermes_cli.runtime_provider.resolve_runtime_provider",
+            lambda: {"provider": "kimi-coding", "api_key": ""},
+        )
+        assert detect_provider() is None
+
+    def test_detect_none_on_resolution_error(self, monkeypatch):
+        def _boom():
+            raise RuntimeError("broken")
+
+        monkeypatch.setattr("hermes_cli.runtime_provider.resolve_runtime_provider", _boom)
+        assert detect_provider() is None