Use one BevyManifest instance in proc macros

[raldone01]

Objective

• Minor consistency improvement in proc macro code.
• Remove get_path_direct since it was only used once anyways and doesn't add much.

Solution

• Possibly a minor performance improvement since the Cargo.toml wont be parsed as often.

Testing

• I don't think it breaks anything.
• This is my first time working on bevy itself. Is there a script to do a quick verify of my pr?

Other PR

Similar to #7536 but has no extra dependencies.

[github-actions]

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[github-actions]

Your PR increases Bevy Minimum Supported Rust Version. Please update the rust-version field in the root Cargo.toml file.

[alice-i-cecile]

Is there a script to do a quick verify of my pr?
Use cargo run -p ci, which runs the ci project in the tools folder :)

[alice-i-cecile]

Looks nice, but as the bot says, you'll need to bump the MSRV. I'm pretty sure that's due to the use of LazyLock here?

[raldone01]

No, the MSRV issue was because I also tried to use CARGO_MANIFEST_PATH instead of CARGO_MANIFEST_DIR which apparently needs a higher MSRV.

I did a quick search but did not find any annotations when it was added exactly, so I just reverted back to using CARGO_MANIFEST_DIR.

As you can see the all the ci runs passed.

[raldone01]

Use cargo run -p ci, which runs the ci project in the tools folder :)

I tried to run the ci scripts by cding into the folder and running them with cargo run.

Consider adding an advisory for cargo run -p ci to the PR-template.

[raldone01]

The pr says waiting on author. Do I have to do anything?

[alice-i-cecile]

Nope, I just forgot to update the label after your response :) This needs a second review then it's good to merge.