9b6413c3de
The broken-link diagnostic severity was already consulted by
collect_diagnostics, but Config.diagnostic was hardcoded to the default and
never populated from initializationOptions/didChangeConfiguration. Parse a
client-supplied `diagnostic.link_severity` ('off'|'hint'|'warn'|'error',
case-insensitive) into LinkSeverity and apply it in both from_init_params and
apply_change. Partial config updates that omit `diagnostic` preserve the
existing severity rather than resetting it.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>