Fix for rad init UI issue on a small terminal (#8068)

# Description

- Removed hard coded values for width and height for list model.
- Dynamically change the width or height of the list model depending on
the terminal dimensions.

## Type of change

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- This pull request fixes a bug in Radius and has an approved issue
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Fixes: #6492

## Contributor checklist
Please verify that the PR meets the following requirements, where
applicable:

- [ ] An overview of proposed schema changes is included in a linked
GitHub issue.
- [ ] A design document PR is created in the [design-notes
repository](https://github.com/radius-project/design-notes/), if new
APIs are being introduced.
- [ ] If applicable, design document has been reviewed and approved by
Radius maintainers/approvers.
- [ ] A PR for the [samples
repository](https://github.com/radius-project/samples) is created, if
existing samples are affected by the changes in this PR.
- [ ] A PR for the [documentation
repository](https://github.com/radius-project/docs) is created, if the
changes in this PR affect the documentation or any user facing updates
are made.
- [ ] A PR for the [recipes
repository](https://github.com/radius-project/recipes) is created, if
existing recipes are affected by the changes in this PR.

---------

Signed-off-by: Vishwanath Hiremath <[email protected]>

pkg/cli/prompt/list/list.go

@@ -26,10 +26,6 @@ import (
 	"github.com/charmbracelet/x/ansi"
 )
 
-const listHeight = 14
-
-const defaultWidth = 400
-
 var (
 	titleStyle        = lipgloss.NewStyle().PaddingLeft(2)
 	itemStyle         = lipgloss.NewStyle().PaddingLeft(4)
@@ -92,7 +88,8 @@ func NewListModel(choices []string, promptMsg string) ListModel {
 		items[i] = item(choice)
 	}
 
-	l := list.New(items, itemHandler{}, defaultWidth, listHeight)
+	// setting width and height of list model to 0, that means its set to terminal width/height.
+	l := list.New(items, itemHandler{}, 0, 0)
 	l.Title = promptMsg
 	l.SetShowStatusBar(false)
 	l.SetFilteringEnabled(true)
@@ -134,6 +131,9 @@ func (m ListModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 	switch msg := msg.(type) {
 	case tea.WindowSizeMsg:
 		m.width = msg.Width
+		// setting the width and height of the list model as terminal dimensions changes.
+		// setting the height to 25% of the height of the terminal height.
+		m.List.SetSize(msg.Width, msg.Height-((3*msg.Height)/4))
 	case tea.KeyMsg:
 		switch keypress := msg.String(); keypress {
 		case "ctrl+c", "q":