🤖 fix: prevent new workspace modal from closing on outside click (#65)

## Changes

Fixes the new workspace modal behavior so it only closes via explicit
user actions (Cancel button, Create Workspace button, or Escape key),
not by clicking outside the modal.

## Problem

Previously, clicking anywhere on the overlay (dark background) would
close the modal, which could lead to accidental dismissal when users are
filling out the form.

## Solution

Removed:
- `onClick={handleCancel}` from `ModalOverlay`
- `onClick={(e) => e.stopPropagation()}` from `ModalContent`

The modal now only closes through:
1. Clicking the Cancel button
2. Clicking Create Workspace (after successful creation)
3. Pressing Escape key (via existing keybind handler)

## Testing

Manual testing needed:
1. Open the new workspace modal
2. Click outside the modal (on the overlay) - should NOT close
3. Click Cancel - should close
4. Open modal again and press Escape - should close
5. Create a workspace successfully - should close

_Generated with `cmux`_

Author: ibetitsmike

src/components/NewWorkspaceModal.tsx

@@ -201,8 +201,8 @@ const NewWorkspaceModal: React.FC<NewWorkspaceModalProps> = ({
   const projectName = projectPath.split("/").pop() ?? projectPath.split("\\").pop() ?? "project";
 
   return (
-    <ModalOverlay onClick={handleCancel}>
-      <ModalContent onClick={(e) => e.stopPropagation()}>
+    <ModalOverlay>
+      <ModalContent>
         <h2>New Workspace</h2>
         <ModalSubtitle>Create a new workspace for {projectName}</ModalSubtitle>