Fix API config tests to use direct API validation

- Change tests to use cfg.API.Config.Validate() instead of full cfg.Validate()
- Prevents Java config validation errors from interfering with API tests
- Update error message assertions to match actual API validation messages
- All tests now pass correctly

Fixes test failures after PR minekube#563 merge.

Author: robinbraemer

pkg/gate/config/api_config_test.go

@@ -23,10 +23,10 @@ api:
 	assert.True(t, cfg.API.Enabled, "API should be enabled")
 	assert.Equal(t, "0.0.0.0:3000", cfg.API.Config.Bind, "API bind should be parsed correctly")
 
-	// Test validation
-	warns, errs := cfg.Validate()
-	assert.Empty(t, errs, "Should have no validation errors")
-	assert.Empty(t, warns, "Should have no validation warnings")
+	// Test API config validation directly (not full config validation)
+	warns, errs := cfg.API.Config.Validate()
+	assert.Empty(t, errs, "Should have no API validation errors")
+	assert.Empty(t, warns, "Should have no API validation warnings")
 }
 
 func TestAPIConfigNested(t *testing.T) {
@@ -46,9 +46,9 @@ api:
 	assert.Equal(t, "", cfg.API.Config.Bind, "API bind should be empty (nested structure not supported with inline)")
 
 	// Test validation (should fail because bind is empty)
-	_, errs := cfg.Validate()
+	_, errs := cfg.API.Config.Validate()
 	assert.NotEmpty(t, errs, "Should have validation errors because nested config is ignored")
-	assert.Contains(t, errs[0].Error(), "api:", "Error should mention API validation")
+	assert.Contains(t, errs[0].Error(), "bind address must not be empty", "Error should mention empty bind")
 }
 
 func TestAPIConfigDisabled(t *testing.T) {
@@ -67,9 +67,9 @@ api:
 	assert.Equal(t, "localhost:8080", cfg.API.Config.Bind, "API bind should still be parsed")
 
 	// Test validation (should pass even when disabled)
-	warns, errs := cfg.Validate()
-	assert.Empty(t, errs, "Should have no validation errors for disabled API")
-	assert.Empty(t, warns, "Should have no validation warnings for disabled API")
+	warns, errs := cfg.API.Config.Validate()
+	assert.Empty(t, errs, "Should have no API validation errors for disabled API")
+	assert.Empty(t, warns, "Should have no API validation warnings for disabled API")
 }
 
 func TestAPIConfigInvalidBind(t *testing.T) {
@@ -88,9 +88,9 @@ api:
 	assert.Equal(t, "invalid-address", cfg.API.Config.Bind, "Invalid bind should be parsed")
 
 	// Test validation (should fail)
-	_, errs := cfg.Validate()
+	_, errs := cfg.API.Config.Validate()
 	assert.NotEmpty(t, errs, "Should have validation errors for invalid bind")
-	assert.Contains(t, errs[0].Error(), "api:", "Error should mention API validation")
+	assert.Contains(t, errs[0].Error(), "invalid bind", "Error should mention invalid bind")
 }
 
 func TestAPIConfigEmptyBind(t *testing.T) {
@@ -109,20 +109,20 @@ api:
 	assert.Equal(t, "", cfg.API.Config.Bind, "Empty bind should be parsed")
 
 	// Test validation (should fail)
-	_, errs := cfg.Validate()
+	_, errs := cfg.API.Config.Validate()
 	assert.NotEmpty(t, errs, "Should have validation errors for empty bind")
-	assert.Contains(t, errs[0].Error(), "api:", "Error should mention API validation")
+	assert.Contains(t, errs[0].Error(), "bind address must not be empty", "Error should mention empty bind")
 }
 
 func TestAPIConfigDefaultSecurity(t *testing.T) {
 	// Test that default config uses localhost (not 0.0.0.0) for security
 	cfg := DefaultConfig
-	
+
 	assert.False(t, cfg.API.Enabled, "API should be disabled by default")
 	assert.Equal(t, "localhost:8080", cfg.API.Config.Bind, "Default API bind should use localhost for security")
-	
+
 	// Test that API config itself is valid (even though full config may have other warnings)
 	apiWarns, apiErrs := cfg.API.Config.Validate()
 	assert.Empty(t, apiErrs, "Default API config should have no validation errors")
 	assert.Empty(t, apiWarns, "Default API config should have no validation warnings")
-}
+}