feat(config): add some more config options (#64)

## Add
Make these things configurable
- Expand aliases
- Suggest hidden files (#59)
- Toggle menu and mode 

```
[ui]
hidden-files = true # or false

[core]
expand-alias = true # or false

[keybindings]
toggle-mode = "ctrl+r"
toggle-menu = "ctrl+space"
```

- Auto reload config on changes: now just changes config and save the
file, IRIS will auto detect and reload in silent
- Added all these in config on init and docs

## Fix
I tested on holding backspace and the ghost text keep glitching so I
fixed it, this is just a small fix

integration/overlay.go

@@ -434,6 +434,24 @@ func (o *Overlay) GetGhostText(buffer string, cursorAtEnd bool) string {
 	return ""
 }
 
+func (o *Overlay) ClearGhostTextState() {
+	o.mu.Lock()
+	defer o.mu.Unlock()
+	o.LastGhostLen = 0
+}
+
+func (o *Overlay) HideGhostTextSync() string {
+	o.mu.Lock()
+	defer o.mu.Unlock()
+	if o.LastGhostLen > 0 {
+		padLen := o.LastGhostLen + 4
+		res := "\0337" + strings.Repeat(" ", padLen) + "\0338"
+		o.LastGhostLen = 0
+		return res
+	}
+	return ""
+}
+
 func (o *Overlay) RenderGhostText(buffer string, userNavigated bool, cursorAtEnd bool) string {
 	o.mu.Lock()
 	defer o.mu.Unlock()
@@ -757,7 +775,7 @@ func (o *Overlay) draw() string {
 	if !isClassic {
 		keyStyle := lipgloss.NewStyle().Foreground(lipgloss.Color("#a277ff")).Bold(true)
 		tabKey := keyStyle.Render("<Tab>")
-		ctrlRKey := keyStyle.Render("<Ctrl+R>")
+		ctrlRKey := keyStyle.Render(config.FormatKeyName(config.Get().Keybindings.ToggleMode))
 		acceptText := lipgloss.NewStyle().Foreground(t.ScrollInfo).Render(" Accept")
 		modeText := lipgloss.NewStyle().Foreground(t.ScrollInfo).Render(" Mode")
 		footerInfo = fmt.Sprintf(" %s%s • %s%s ", tabKey, acceptText, ctrlRKey, modeText)