Added registry lookup at top of renderWidget() before hardcoded switch. Custom widgets registered via engine.registerWidget(type:factory) are now rendered by the factory closure, enabling app-level extensions.
- Core: Schema (Codable), Store, EventBus, RPC, Engine, I18n - Controls: Text, Title1-6, Label, Input, Textarea, Number, Date, Button, Select VBox, HBox, ScrollPanel, DynamicColumn, Tabular, Form, InlineForm, TabView, Menu, PopupWindow, Html, Image, UrlWidget - Renderer: BricksView (main entry), ControlRenderer (recursive dispatch) - 30+ widget types, 9 bind actiontypes - Form validation (required/minlength/maxlength/min/max/email/number/pattern) - i18n with multi-language JSON files - 18 tests covering schema parsing, store, i18n, events
