No way to access compilation output files

### Command

build, serve

### Description

I have an esbuild plugin that is resposible to collect outputFiles after compilation (using `onEnd` hook with `result.outputFiles`).

When using application builder (esbuild) with custom plugins there is no way to access full list of outputFiles, only those emitted by `main` entrypoint compilation. There is no way to access additional files emited by angular builder, such as `polyfills`, assets, styles etc.

Previously, with using webpack plugin, i was able to get full list of outputFiles by using `processAssets` compilation hook.

I need to list emited files, as this is only way to get full names with filenames hash.

MY point is to build something like manifest of compilation result output files.

### Describe the solution you'd like

I would like to be able to access all compilation files by esbuild plugin.

### Describe alternatives you've considered

An alternative could be to access output files as an result of builder output, currently `build` command only returns `{success: true}` without information about output files.

Start with the application builder's build and serve paths and the esbuild plugin's onEnd hook, then inspect how result.outputFiles is currently exposed. Determine how the full emitted set, including polyfills, assets, and styles, or the build command result should expose filenames with hashes. Done means a plugin or builder consumer can access all compilation output files for a manifest.

Written by the indexing model from the issue text.