Cake5 - #12

…grated tables.

…oalTS migrated tables."

This reverts commit 36df973.

…back

Underscore-prefixed serialization view variables are removed in CakePHP 5.
This makes every special parameter (serialize, url, entities, include,
fieldsets, links, meta, jsonOptions) readable from BOTH forms:
viewBuilder()->setOption('serialize', ...) - preferred, Cake-5-compatible -
and the legacy $this->set('_serialize', ...), which keeps working unchanged.

Fully backward compatible on CakePHP 4.x: options arrive via the View
constructor's viewOptions and land in view config (View::__construct
setConfig), so getConfig() reads them; when no option is set behaviour is
byte-identical to before. This unblocks consumers migrating their set('_*')
call sites ahead of the CakePHP 5 switch.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

- View::$viewVars is removed in Cake 5: all special-parameter reads go
  through the option/get() dual read; _dataToSerialize enumerates
  getVars() instead of diffing the viewVars array.
- Cake\Core\Exception\Exception alias is removed: MissingViewVarException
  extends CakeException with the typed $_messageTemplate.
- Constructor takes Cake 5's nullable-typed parameters; render() matches
  the Cake 5 parent signature.
- Requires cakephp ^5.0, php >=8.2. neomerx/json-api 0.6.5 is unchanged -
  response documents stay byte-identical.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>