GeezerVison

…pers (#30508)

Adds two small helpers to `cli/cliui/output.go` so commands that add
`-o/--output` don't repeat the same boilerplate, as suggested in
#30152 (comment) by
@jeremyruppel.

- `TextFormatFunc[T]` wraps `ChangeFormatterData(TextFormat(), ...)`
with the type assertion and "expected X, got Y" error, so a command only
supplies its render function.
- `(*OutputFormatter).WriteLine` formats data and writes it to an
`io.Writer` with a trailing newline, replacing the `Format` + `Fprintln`
block.

No existing callers change in this PR. These PRs are stacked on it and
use the helpers:

- #30135 `coder tokens create`
- #30139 `coder ai-gateway keys create`
- #30145 `coder organizations members edit-roles`
- #30152 `coder provisioner keys create`

Migrating the existing callers on `main` (for example
`cli/organization.go`, `enterprise/cli/workspaceproxy.go`) is left for a
follow-up, since some of them print with `Fprint` rather than `Fprintln`
and need care to keep output identical.

Refs CLI-56

<details>
<summary>Decision log</summary>

- A global `-o` flag on the root command was ruled out because `coder
config-ssh` already uses `-o` for `--ssh-option`.
- The "one-time secret plus metadata" response structs in #30135 and
#30152 stay local to each command, since they embed different SDK types
and a shared helper would save little.
- `WriteLine` uses `Fprintln` to match the four stacked PRs and most
existing callers.
It was renamed from `Write` during review so the trailing newline is
visible at call sites and the method is not confused with `io.Writer`.

</details>

> [!NOTE]
> This PR was generated by Coder Agents on behalf of @nickvigilante.