Only include files when packaging bevy, rather than excluding

[LikeLakers2]

Objective

Reduce the size of .crate files generated by cargo package or cargo publish for the bevy package.

Solution

Change what files are included in a .crate file, by only including necessary folders and files, rather than excluding a few specific folders and keeping the rest.

As a result of this change, several files and folders are no longer included in the generated .crate files:

• .cargo/ - Only contains config_fast_builds.toml, which does nothing unless renamed to config.toml
• docs-template/ - Only used for generating documentation
• examples/wasm/ - Does not contain any examples that would be scraped by rustdoc.
• examples/no_std/README.md, examples/stress_tests/README.md, examples/README.md - These README files aren't used anywhere in the docs, so they just take up space in the .crate
• working-migration-guides/, working-release-notes/ - These are only relevant for building up documentation that will be released alongside 0.16 proper.
• .gitattributes, .gitignore - Only used for the repo, and have no effect on how Cargo handles the package
• clippy.toml, deny.toml, rustfmt.toml, typos.toml - Only relevant when developing Bevy
• CODE_OF_CONDUCT.md, CONTRIBUTING.md, CREDITS.md - Only relevant in their latest form as contained on the repo (so there's not much point to packaging these up, since they can quickly become outdated)

Testing

This change was tested following these steps:

1. Run cargo package at the root of the repo
2. Rename the resulting .crate file so it isn't overwritten later
3. Insert the changes from this PR into /Cargo.toml
4. Run cargo package at the root of the repo
5. Compare the resulting .crate file sizes

I performed my testing on Windows 10 22H2, with Rust 1.85.1, using commit 0d90da8. Only one change was made from this commit that was unrelated to testing: The removal of an instance of "bevy_internal/bevy_anti_aliasing" from /Cargo.toml. This was done because Cargo would complain about the use of a non-existent feature otherwise - I do not believe it affects the results in any major way.

[mockersf]

Can you keep the tests and examples as included? They are used as compilation tests front the crates, and examples are used when building docs on docs.rs

[LikeLakers2]

@mockersf Done.

I will admit, I'm a little bothered by how this brings the resulting file size back up to nearly 600 KB. It's not so bad since it's only downloaded once by Cargo, and I understand the examples are used by the docs, but it still feels... weird to me.

[greeble-dev]

Clicking approve as I've done some basic tests and didn't spot any problems.

Tested cargo package on Win10. I also unpacked the crate and made a new crate with a path dependency on the unpacked folder. I replaced the new crate's main.rs with the 3d_scene example and confirmed it built and ran.

[cart]

One consideration is that switching to includes introduces a new failure case (failing to include something necessary). Given that the size wins are marginal here (8KB), I'm not sure thats worth the added risk. Trimming out "big" things with excludes seems like the better tradeoff.

[mockersf]

sticking to exclude for now