refactor: trim config type exports

src/config/context-visibility.ts

@@ -8,7 +8,7 @@ type ChannelContextVisibilityConfig = {
   accounts?: Record<string, { contextVisibility?: ContextVisibilityMode }>;
 };
 
-export type ContextVisibilityDefaultsConfig = {
+type ContextVisibilityDefaultsConfig = {
   channels?: {
     defaults?: {
       contextVisibility?: ContextVisibilityMode;

src/config/defaults.ts

@@ -84,7 +84,7 @@ export function resolveNormalizedProviderModelMaxTokens(params: {
   return Math.min(safeMaxTokens, params.contextWindow);
 }
 
-export type SessionDefaultsOptions = {
+type SessionDefaultsOptions = {
   warn?: (message: string) => void;
   warnState?: WarnState;
 };

src/config/env-substitution.ts

@@ -80,7 +80,7 @@ export type EnvSubstitutionWarning = {
   configPath: string;
 };
 
-export type SubstituteOptions = {
+type SubstituteOptions = {
   /** When set, missing vars call this instead of throwing and the original placeholder is preserved. */
   onMissing?: (warning: EnvSubstitutionWarning) => void;
 };