feature(customware): add component context menu bundle

[Magaav]

Summary

Adds a reference Customware Bundle Interface plugin for component-level context menus.

This is intentionally implemented as an installable customware bundle, not as Space Agent core behavior. It demonstrates how browser-side UI evolution can live behind space.bundle.yaml plus documented ext/js hooks while remaining removable and update-friendly.

What Changed

• Adds tests/fixtures/component_context_menu_bundle/ as an installable reference bundle.
• Declares space/component-context-menu with component-menu, actions, and browser-runtime capabilities.
• Loads through _core/framework/initializer.js/initialize/end.
• Installs space.componentMenu.registerAction(...) for custom component actions.
• Adds a right-click menu for Space widget cards discovered through .spaces-widget-card and data-widget-id.
• Keeps a footer Copy ID action so users can paste the exact UI entity id into Agent Space.

Why

Downstream teams need a safe way to attach precise UI actions without monkey patching Space Agent runtime files. Copy ID is especially useful because it lets a user right-click a widget/component, copy its stable id, and tell Agent Space exactly what to change.

Validation

• node --input-type=module --check < tests/fixtures/component_context_menu_bundle/component-menu.js
• node --input-type=module --check < tests/fixtures/component_context_menu_bundle/ext/js/_core/framework/initializer.js/initialize/end/component-context-menu.js
• node --test tests/customware_bundle_test.mjs

Notes

This PR is stacked on #44 because the plugin depends on bundle manifest discovery and the browser-side bundle runtime.