Use one BevyManifest instance per crate in proc macros

[mdickopp]

Objective

Fixes #17004

Solution

Store BevyManifest instances in a hash map keyed on the value of the CARGO_MANIFEST_DIR environment variable. This causes one BevyManifest instance per crate to be created.

Testing

• It fixes rust-analyzer autocomplete is broken for some ECS types #17004.
• Building bevy with cargo build works.

[mdickopp]

Closing in favor of #17330.