Expose ensureTable on plugin scope

[Baijack-star]

Summary

• add scope.ensureTable(options) for the new handleApplication(scope) plugin API
• preserve the legacy ensureTable behavior of stamping the component origin before delegating to table(options)
• pass the loader's origin into Scope and cover it with a component-loader unit test

Why

Issue #607 notes that plugins migrating from the old start / startOnMainThread API lose access to the legacy ensureTable helper. The old helper did:

options.origin = origin;
return table(options);

This keeps that same behavior available from handleApplication(scope) as scope.ensureTable(options).

Verification

• npm_config_cache=/tmp/npm-cache-harper-ensuretable npm ci --ignore-scripts
• npm run build
• node --expose-internals --enable-source-maps --experimental-vm-modules - <<'NODE' ... NODE running unitTests/components/componentLoader.test.js with grep /ensureTable/ after initTestEnvironment()
• npm run lint:required -- components/Scope.ts components/componentLoader.ts unitTests/components/componentLoader.test.js
• git diff --check

Note: running ./node_modules/.bin/mocha unitTests/components/componentLoader.test.js --grep ensureTable directly failed before the test loaded because the component loader imports modules that expect the unit-test environment to be initialized. The programmatic Mocha run initializes environmentManager.initTestEnvironment() first and the new test passes.

I used an AI coding assistant to prepare this patch.

Fixes #607