Fix deploy not working when using --no-build

[isaacroldan]

Why

app deploy --no-build used a separate copy path that no longer matched the extension bundle build path.

What

• Route deploy bundling through buildForBundle and pass skipBuild through.
• Make UI and function builders reuse existing output when skipBuild is set.
• Remove copyIntoBundle and update bundle tests.

Testing

• pnpm vitest packages/app/src/cli/services/deploy/bundle.test.ts packages/app/src/cli/models/extensions/extension-instance.test.ts --run
• pnpm --filter @shopify/app lint
• pnpm --filter @shopify/app type-check

[isaacroldan]

• Fix deploy not working when using --no-build #7903 👈 (View in Graphite)
• main

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