* feat(CommandsEnum.ts): add COMMANDS enum

* refactor(api.ts): use CONFIG_MODES enum from config.ts
* refactor(config.ts): use COMMANDS and CONFIG_MODES enums, extract validateConfig function
* feat(config.ts): add CONFIG_MODES enum and refactor configCommand function to use it

* refactor(githook.ts): import COMMANDS enum from CommandsEnum.js file

src/CommandsEnum.ts

@@ -0,0 +1,4 @@
+export enum COMMANDS {
+  config = 'config',
+  hook = 'hook'
+}