fix(config): reload .env over stale shell overrides

Hermes startup entrypoints now load ~/.hermes/.env and project fallback env files with user config taking precedence over stale shell-exported values. This makes model/provider/base URL changes in .env actually take effect after restarting Hermes. Adds a shared env loader plus regression coverage, and reproduces the original bug case where OPENAI_BASE_URL and HERMES_INFERENCE_PROVIDER remained stuck on old shell values before import.

tests/hermes_cli/test_env_loader.py

@@ -0,0 +1,70 @@
+import importlib
+import os
+import sys
+from pathlib import Path
+
+from hermes_cli.env_loader import load_hermes_dotenv
+
+
+def test_user_env_overrides_stale_shell_values(tmp_path, monkeypatch):
+    home = tmp_path / "hermes"
+    home.mkdir()
+    env_file = home / ".env"
+    env_file.write_text("OPENAI_BASE_URL=https://new.example/v1\n", encoding="utf-8")
+
+    monkeypatch.setenv("OPENAI_BASE_URL", "https://old.example/v1")
+
+    loaded = load_hermes_dotenv(hermes_home=home)
+
+    assert loaded == [env_file]
+    assert os.getenv("OPENAI_BASE_URL") == "https://new.example/v1"
+
+
+def test_project_env_overrides_stale_shell_values_when_user_env_missing(tmp_path, monkeypatch):
+    home = tmp_path / "hermes"
+    project_env = tmp_path / ".env"
+    project_env.write_text("OPENAI_BASE_URL=https://project.example/v1\n", encoding="utf-8")
+
+    monkeypatch.setenv("OPENAI_BASE_URL", "https://old.example/v1")
+
+    loaded = load_hermes_dotenv(hermes_home=home, project_env=project_env)
+
+    assert loaded == [project_env]
+    assert os.getenv("OPENAI_BASE_URL") == "https://project.example/v1"
+
+
+def test_user_env_takes_precedence_over_project_env(tmp_path, monkeypatch):
+    home = tmp_path / "hermes"
+    home.mkdir()
+    user_env = home / ".env"
+    project_env = tmp_path / ".env"
+    user_env.write_text("OPENAI_BASE_URL=https://user.example/v1\n", encoding="utf-8")
+    project_env.write_text("OPENAI_BASE_URL=https://project.example/v1\nOPENAI_API_KEY=project-key\n", encoding="utf-8")
+
+    monkeypatch.setenv("OPENAI_BASE_URL", "https://old.example/v1")
+    monkeypatch.delenv("OPENAI_API_KEY", raising=False)
+
+    loaded = load_hermes_dotenv(hermes_home=home, project_env=project_env)
+
+    assert loaded == [user_env, project_env]
+    assert os.getenv("OPENAI_BASE_URL") == "https://user.example/v1"
+    assert os.getenv("OPENAI_API_KEY") == "project-key"
+
+
+def test_main_import_applies_user_env_over_shell_values(tmp_path, monkeypatch):
+    home = tmp_path / "hermes"
+    home.mkdir()
+    (home / ".env").write_text(
+        "OPENAI_BASE_URL=https://new.example/v1\nHERMES_INFERENCE_PROVIDER=custom\n",
+        encoding="utf-8",
+    )
+
+    monkeypatch.setenv("HERMES_HOME", str(home))
+    monkeypatch.setenv("OPENAI_BASE_URL", "https://old.example/v1")
+    monkeypatch.setenv("HERMES_INFERENCE_PROVIDER", "openrouter")
+
+    sys.modules.pop("hermes_cli.main", None)
+    importlib.import_module("hermes_cli.main")
+
+    assert os.getenv("OPENAI_BASE_URL") == "https://new.example/v1"
+    assert os.getenv("HERMES_INFERENCE_PROVIDER") == "custom"