This update contains only packaging updates and fixes and no actual code changes:

• Simplify packaging of parsec, parsec-tool, and dbus-parsec and update to more recent Rust packaging standards. This includes dropping outdated workarounds for build issues that are no longer required (which in turn had started causing their problems).
• As a side effect, these packages are now built with the default Fedora compiler flags for Rust code, resulting in binaries that are likely slightly smaller, run a bit faster, and have way better debug symbols.
• Update packaging of the parsec-client, parsec-interface, prost-build, and secrecy crates to the latest Rust packaging standards. This includes changes to drop unused subpackages for optional features with missing dependencies (i.e. fix FailsToInstall bugs).
• Add a dependency on protobuf-compiler to the prost-build crate at both build-time and install-time so dependent packages don't need to all do this manually.