Separate line number logic from editor view model

[dev-ant]

🔨 Refactoring Target

• EditorViewModel.kt

📝 Description

• Separate line number logic from editor view model
• I think it unnecessary to editor view model contains line number logic

✅ Tasks

• refactor(util): add line number manager class
• refactor(editor): separate line number logic to util
• refactor(editor): reduce line number update logic call
• refactor(editor): separate render fun to after text changed fun

🎯 Expected Outcome after Refactoring

• ensure SoC of editor view model