feat(activity): multi-service config, make help default, install-cli

Bare make lists targets. make install-cli installs the activity tool via uv.
Named activity-core backends live in ~/.config/activity/services.json with
list/add/use/default/which; -s/--service selects one call without changing
the default; --activity-url is a one-shot override.

tests/test_review_cli_services.py

@@ -0,0 +1,127 @@
+"""Tests for multi-service activity-core endpoint config."""
+
+from __future__ import annotations
+
+import json
+from pathlib import Path
+
+import pytest
+
+from activity_core.review_cli import services as svc
+from activity_core.review_cli.main import main
+from activity_core.review_cli.sources import (
+    activity_core_url,
+    apply_endpoint_overrides,
+    clear_endpoint_overrides,
+    state_hub_url,
+)
+
+
+def test_add_list_use_service(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
+    monkeypatch.setenv("ACTIVITY_CONFIG_DIR", str(tmp_path))
+    path = svc.config_path(tmp_path)
+    cfg = svc.add_service(
+        "railiance",
+        activity_core_url="https://activity.coulomb.social/",
+        state_hub_url="http://127.0.0.1:18000",
+        description="prod",
+        make_default=True,
+        path=path,
+    )
+    assert cfg["default"] == "railiance"
+    assert cfg["services"]["railiance"]["activity_core_url"] == "https://activity.coulomb.social"
+
+    svc.add_service(
+        "local",
+        activity_core_url="http://127.0.0.1:8010",
+        path=path,
+    )
+    svc.set_default("local", path)
+    cfg = svc.load_config(path)
+    assert cfg["default"] == "local"
+
+    ep = svc.resolve_endpoints(config_path_override=path)
+    assert ep["source"] == "default"
+    assert ep["service"] == "local"
+    assert ep["activity_core_url"] == "http://127.0.0.1:8010"
+
+    ep2 = svc.resolve_endpoints(service="railiance", config_path_override=path)
+    assert ep2["source"] == "service"
+    assert ep2["activity_core_url"] == "https://activity.coulomb.social"
+    assert ep2["state_hub_url"] == "http://127.0.0.1:18000"
+
+    ep3 = svc.resolve_endpoints(
+        service="railiance",
+        activity_url="http://override:9",
+        config_path_override=path,
+    )
+    assert ep3["source"] == "flag"
+    assert ep3["activity_core_url"] == "http://override:9"
+
+
+def test_env_beats_default(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
+    path = svc.config_path(tmp_path)
+    svc.add_service(
+        "railiance",
+        activity_core_url="https://activity.coulomb.social",
+        make_default=True,
+        path=path,
+    )
+    monkeypatch.setenv("ACTIVITY_CORE_URL", "http://env-only:8010")
+    ep = svc.resolve_endpoints(config_path_override=path)
+    assert ep["source"] == "env"
+    assert ep["activity_core_url"] == "http://env-only:8010"
+
+
+def test_service_flag_beats_env(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
+    path = svc.config_path(tmp_path)
+    svc.add_service(
+        "railiance",
+        activity_core_url="https://activity.coulomb.social",
+        path=path,
+    )
+    monkeypatch.setenv("ACTIVITY_CORE_URL", "http://env-only:8010")
+    ep = svc.resolve_endpoints(service="railiance", config_path_override=path)
+    assert ep["source"] == "service"
+    assert ep["activity_core_url"] == "https://activity.coulomb.social"
+
+
+def test_apply_endpoint_overrides() -> None:
+    clear_endpoint_overrides()
+    apply_endpoint_overrides("http://x:1", "http://y:2")
+    assert activity_core_url() == "http://x:1"
+    assert state_hub_url() == "http://y:2"
+    clear_endpoint_overrides()
+
+
+def test_cli_service_add_and_which(
+    tmp_path: Path, monkeypatch: pytest.MonkeyPatch, capsys: pytest.CaptureFixture[str]
+) -> None:
+    monkeypatch.setenv("ACTIVITY_CONFIG_DIR", str(tmp_path))
+    code = main(
+        [
+            "service",
+            "add",
+            "railiance",
+            "--url",
+            "https://activity.coulomb.social",
+            "--hub-url",
+            "http://127.0.0.1:18000",
+            "--make-default",
+        ]
+    )
+    assert code == 0
+    capsys.readouterr()  # drop add text
+    code = main(["service", "list", "--format", "json"])
+    assert code == 0
+    data = json.loads(capsys.readouterr().out)
+    assert data["default"] == "railiance"
+    assert "railiance" in data["services"]
+
+    code = main(
+        ["service", "which", "--service", "railiance", "--format", "json"]
+    )
+    assert code == 0
+    which = json.loads(capsys.readouterr().out)
+    assert which["activity_core_url"] == "https://activity.coulomb.social"
+    assert which["source"] == "service"