feat: add sdkOptions passthrough for Sentry SDK client options

[gradinarufelix]

Adds a Flownative.Sentry.sdkOptions settings map whose entries are passed to \Sentry\init(), so projects can configure any YAML-representable SDK option (e.g. max_request_body_size, send_default_pii) without a package change.

Flownative:
  Sentry:
    sdkOptions:
      max_request_body_size: 'never'
      send_default_pii: false

• Options the package sets explicitly always take precedence (array_replace($sdkOptions, $typedOptions)), so existing settings like sampleRate cannot be silently overridden.
• before_send, before_send_transaction, before_send_check_in, before_send_log, before_send_metrics, ignore_exceptions and integrations are reserved and rejected at boot with an exception naming the offending settings path — they are managed by the package (and callables cannot be expressed in YAML anyway).
• in_app_exclude entries are merged with the package defaults instead of replacing them.
• Empty by default: unconfigured behavior is byte-for-byte unchanged.

Which options are valid depends on the installed sentry/sentry version; the README documents this.

Background: we roll out Sentry to privacy-sensitive customers and need max_request_body_size: 'never' (form submissions must not be attached to events) configurable per project without forking.