Keep PHP diagnostics out of WP-CLI stdout

## Problem

`studio wp` can emit PHP 8.5 deprecations on stdout before command output. This corrupts machine-readable JSON and scalar results consumed by automation, even when the underlying WP-CLI command returns a valid contract.

The reprint runner already configures `error_reporting` and routes displayed errors to stderr, but `apps/cli/lib/run-wp-cli-command.ts` only configures SSL and `allow_url_fopen`.

## Reproduction

1. Run Studio with PHP 8.5.
2. Execute a WP-CLI command that loads the bundled React Promise code, such as `studio wp --help`.
3. Observe `Deprecated: Case statements followed by a semicolon...` on stdout before the command output.

## Expected

WP-CLI stdout contains only command output. PHP diagnostics are suppressed according to the CLI policy or routed to stderr. Add focused coverage for the configured PHP ini entries.

## AI assistance disclosure

GPT-5.6 Sol, via OpenCode, traced a downstream control-plane failure to Studio’s WP-CLI PHP configuration, compared it with the existing reprint configuration, and drafted this issue under human direction.