TOON and pretty output lack a trailing newline

## Bug

`-o toon` and the default `pretty` output don't end with a trailing newline, so the shell prompt (or the next command's output) glues onto the last line.

## Root cause (Speakeasy)

The generated formatters emit toon via `fmt.Fprint` (no newline), and the generated pretty printer doesn't guarantee a final newline. JSON and YAML already terminate correctly.

## Stopgap fix (retire when upstream is fixed)

Three patches under `.speakeasy/patches/internal/output/`:
- `output.go.patch` — toon (both the `Result` and `--include-headers` paths) uses `fmt.Fprintln(out, strings.TrimRight(toonStr, "\n"))`.
- `pretty.go.patch` — `prettyPrint` buffers, then writes with exactly one trailing newline (idempotent).
- `outputitems.go.patch` — the streaming toon path (`--all`) matches.

**To retire:** once the generated formatters emit a single trailing newline, drop those hunks.

## Refs

- Introduced by #23
- Upstream: file to speakeasy-api/speakeasy (generated output formatters).

Start by reading the three patches under .speakeasy/patches/internal/output/: output.go.patch, pretty.go.patch, and outputitems.go.patch, covering normal, header, pretty, and streaming paths. Run the CLI with -o toon, default pretty output, and --all to confirm the prompt no longer glues to the output; done means each emits exactly one trailing newline while JSON and YAML remain unchanged.

Written by the indexing model from the issue text.