fix: ensure config_from_env test is isolated and reliable

- Added explicit cleanup of pre-existing environment variables
- Clear default config data in from_env method
- Added more explicit comments about behavior
- Made test environment more isolated

This should fix the CI/CD test failures where the environment
config test was failing with unexpected values.

src/config.rs

@@ -180,6 +180,7 @@ impl Config {
     pub fn from_env() -> Result<Self> {
         let mut config = Self::default();
 
+        // Create a clean environment-only config
         if let Ok(api_key) = env::var("STRAINER_API_KEY") {
             config.api.api_key = Some(api_key);
         }
@@ -200,6 +201,9 @@ impl Config {
             config.limits.tokens_per_minute = Some(tpm.parse()?);
         }
 
+        // Clear any pre-existing provider-specific data that might have come from default
+        config.api.provider_specific.clear();
+
         Ok(config)
     }
 

tests/config_test.rs

@@ -78,7 +78,18 @@ impl Drop for EnvGuard {
 
 #[test]
 fn test_config_from_env() -> Result<()> {
-    // Set test environment variables first
+    // First, clear any existing environment variables
+    for var in &[
+        "STRAINER_API_KEY",
+        "STRAINER_PROVIDER",
+        "STRAINER_BASE_URL",
+        "STRAINER_REQUESTS_PER_MINUTE",
+        "STRAINER_TOKENS_PER_MINUTE",
+    ] {
+        env::remove_var(var);
+    }
+
+    // Set test environment variables
     env::set_var("STRAINER_API_KEY", "env-key");
     env::set_var("STRAINER_PROVIDER", "anthropic");
     env::set_var("STRAINER_BASE_URL", "https://env.api.com");
@@ -94,7 +105,7 @@ fn test_config_from_env() -> Result<()> {
         "STRAINER_TOKENS_PER_MINUTE",
     ]);
 
-    // Create config from environment
+    // Create a fresh config from environment
     let config = Config::from_env()?;
 
     // Verify the config values directly