feat: implement item management handlers with corresponding tests

internal/handlers/textInputHandler.go

@@ -0,0 +1,42 @@
+package handlers
+
+import (
+	"github.com/StevanFreeborn/term-tier/internal/state"
+	tea "github.com/charmbracelet/bubbletea"
+)
+
+type textInputHandler struct {
+	keys        []string
+	description string
+}
+
+func NewTextInputHandler() KeyMsgHandler {
+	return textInputHandler{
+		keys:        []string{},
+		description: "",
+	}
+}
+
+func (h textInputHandler) KeysHandled() []string {
+	return h.keys
+}
+
+func (h textInputHandler) Description() string {
+	return h.description
+}
+
+func (h textInputHandler) Match(s state.State, msg tea.KeyMsg) bool {
+	return s.Mode() == state.InputMode
+}
+
+func (h textInputHandler) Handle(s state.State, msg tea.KeyMsg) tea.Cmd {
+	switch msg.String() {
+	case "esc":
+		s.ExitInputMode()
+		return nil
+	case "enter":
+		return s.SubmitInput()
+	default:
+		return s.UpdateInput(msg)
+	}
+}