context error is swallowed up, preventing errors.Is

[goodevilgenius]

Describe the bug
I should be able to use errors.Is to check the error returned by the context after p.Run. But that's broken.

Setup
Please complete the following information along with version numbers, if applicable.

• OS Any
• Shell Any
• Terminal Emulator Any
• Terminal Multiplexer Any

To Reproduce
Steps to reproduce the behavior:
See source code

Source Code

ctx := context.WithDeadline(context.Background, time.Second*5)
p := tea.NewProgram(model, tea.WithContext(ctx))
_, err := p.Run()
if errors.Is(err, context.DeadlineExceeded) {
  // Handle timeout
}

Expected behavior
If the five seconds pass during run (in this example), that if block should be executed.

Additional context

bubbletea/tea.go

Line 598 in 9f015c5

err = fmt.Errorf("%w: %s", ErrProgramKilled, p.ctx.Err())

On L598, change the format to "%w: %w", and that should work.