63c23e9ac9
Changes: - Add Rust caching (Swatinem/rust-cache) to all heavy build jobs - Reduce cargo-check-each-crate from 7 to 4 parallel jobs - Reduce tests-linux-stable matrix from 6 to 3 jobs - Set CARGO_INCREMENTAL=0 for consistent caching - Reduce timeouts from 60 to 45 minutes (cache makes builds faster) - Remove redundant disk cleanup steps (cache handles this) Expected improvements: - 50-80% faster builds after cache is populated - Lower VPS load (fewer parallel jobs) - More consistent build times Affected workflows: - checks.yml (cargo-clippy, check-try-runtime) - tests.yml (quick-benchmarks, cargo-check-all-benches) - tests-misc.yml (test-pezframe-ui, cargo-check-each-crate) - tests-linux-stable.yml (test-linux-stable) - docs.yml (test-doc, build-rustdoc)