Add a justfile for the common fcry developer commands. The run recipe is
variadic and uses just positional arguments so program flags are forwarded
through cargo run without needing a second separator.
Keep the default release profile debuggable and checked, then move the
stripped, LTO-enabled artifact settings into the production profile. This
keeps day-to-day release builds easier to inspect while preserving an explicit
production build recipe for optimized distributable binaries.
The clippy recipe uses workspace, all-target, all-feature coverage and denies
warnings so the task runner matches the stricter local verification path.
Test Plan:
- cargo clippy
- cargo clippy --benches
- cargo clippy --tests
- cargo +nightly fmt
- just --fmt --check
- just run --help
- just clippy
- git diff --cached --check
Refs: none
