Gnome: register custom GTypes before templates

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Problem

After #103 (dependency + oxc formatter bump), running yarn && yarn build && yarn start aborts while building the main window with:

Gtk-CRITICAL: Error building template class 'Learn' ...: Invalid object type 'TutorialView'
Gtk-CRITICAL: Error building template class 'Editor' ...: Invalid object type 'QuickHelpView'
... Custom constructor for class Learn returned NULL ...
TypeError: can't access property "events", this._sourceView is null

No usable window opens. Fixes #106.

Root cause

Blueprint templates reference custom widgets by their GTypeName (e.g. $TutorialView, $QuickHelpView, $SourceView). A custom type must be registered with the GObject type system before any template embedding it is instantiated.

Each widget module self-registers via its static GObject.registerClass(...) block (plus a trailing GObject.type_ensure(...)), but that code only runs if the module is actually evaluated. Several consumers import their child widgets with import type { ... } (e.g. main.window.ts imports Learn/Editor/GameConsole/Debugger as types). The bundler strips type-only imports entirely, so those modules were never pulled into the bundle and never registered. The dependency/formatter bump in #103 changed the bundling so the latent bug started biting.

The rebuilt binary grew from ~531 KB to ~731 KB, confirming the widget modules were previously being tree-shaken out.

Fix

Add src/register-types.ts, a side-effect import barrel for every self-registering widget/view/dialog module, loaded early from main.ts (before Application is constructed). This guarantees all GTypes exist before the first window template is built.

Verification

• yarn check:typescript (gjsify tsc) passes.
• yarn check:format passes.
• App starts cleanly (default locale and Hebrew/RTL LC_ALL=he_IL.UTF-8 LANGUAGE=he): no Invalid object type, no returned NULL, no related JS errors; all views (learn/editor/debugger/game console) build and the simulator runs.