[Flight] Add a cached 3rd-party component to the Flight fixture

[unstubbable]

This should allow us to visualize what #33438 is trying to convey.

An uncached 3rd-party component is displayed like this in the dev tools:

However, when the component is restored from a cache, it looks like this:

The Server Components ⚛ track is missing completely here, and the Loading profile... phase also took way longer than without caching the 3rd-party component.

On main, the Server Components ⚛ track is not missing:

The cached 3rd-party component starts before the current render, and is also not excluded here, which is of course expected without #33438.

[react-sizebot]

Comparing: 93f1668...7fc7f64

Critical size changes

Includes critical production bundles, as well as any change greater than 2%:

Name	+/-	Base	Current	+/- gzip	Base gzip	Current gzip
oss-stable/react-dom/cjs/react-dom.production.js	=	6.68 kB	6.68 kB	+0.05%	1.83 kB	1.83 kB
oss-stable/react-dom/cjs/react-dom-client.production.js	=	530.07 kB	530.07 kB	=	93.57 kB	93.57 kB
oss-experimental/react-dom/cjs/react-dom.production.js	=	6.69 kB	6.69 kB	=	1.83 kB	1.83 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js	=	651.16 kB	651.16 kB	=	114.70 kB	114.70 kB
facebook-www/ReactDOM-prod.classic.js	=	676.11 kB	676.11 kB	=	118.97 kB	118.97 kB
facebook-www/ReactDOM-prod.modern.js	=	666.39 kB	666.39 kB	=	117.36 kB	117.36 kB

Significant size changes

Includes any change greater than 0.2%:

(No significant changes)

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