Upstream issues: fixes and features in other tools that would benefit Pavex

[LukeMathWalker]

This is a meta-issue to keep track of feature requests/bugs in other projects that affect Pavex.

• IDE experience:

  • Auto-completion and go-to-definition inside the f! macro
    • https://github.com/rust-lang/rust-analyzer/issues/14999
      • Blocked on https://github.com/rust-lang/rust/issues/66079
    • https://github.com/intellij-rust/intellij-rust/issues/10543)

• Pavex's CLI performance:

  • https://github.com/rust-lang/cargo/issues/12103