In practice this will forbid unused dependencies because we run clippy
with `--deny warnings`.
Workspace lints is a nice place to ratchet up lints through the codebase
all at once and consistently.
Change FromRawTracepointArgs::arg to return T rather than *const T which
seems to have been returning a dangling pointer.
Arguably this is not strictly necessary; edition 2024 seems to be
focused on increased strictness around unsafe code which doesn't unlock
new functionality for our users. That said, this work revealed an
apparent bug (see above) that we wouldn't otherwise catch due to
allow-by-default lints.
The const-assert crate doesn't even compile with stable rust, so we
shouldn't depend on it. Instead we replicate its functionality behind
cfg(unstable) which is set at build time based on the toolchain in use.