relnotes: add 6.6rc0

branching: merge default into stable for 6.6rc0

unstable: do not consider internal phases when computing unstable The revisions that are not part of the "working" set by other means should not be considered for the evolution related computation. This impact the test introduced in 5f9af8422b31 as this is actually a more semantic fix of the issue.

unstable: use the `_mutablerevs` function when computing content divergent This is a useful function to get the revision relevant to these computation, lets make sure all code use it, so that we can improve that `_mutablerevs` function in a later changeset.

unstable: use the `_mutablerevs` function when computing phase divergent This is a useful function to get the revision relevant to these computation, lets make sure all code use it, so that we can improve that `_mutablerevs` function in a later changeset.

rust: add explicit resolver field to top-level cargo manifest file Since Rust 1.51.0, Cargo has support for a better dependency resolver. Workspace packages (like ours) need to explicitely set the field, so let's. https://doc.rust-lang.org/edition-guide/rust-2021/default-cargo-resolver.html

rust: run a clippy pass with the latest stable version Our current version of clippy is older than the latest stable. The newest version has new lints that are moslty good advice, so let's apply them ahead of time. This has the added benefit of reducing the noise for developpers like myself that use clippy as an IDE helper, as well as being more prepared for a future clippy upgrade.

rust-clippy: ignore clippy's recommendation for "useless" cast See explanation inline.

branching: merge stable into default

Added signature for changeset c083d9776cb2