ci: make CI genuinely green — rust-ci toolchain pin + fmt/clippy (#45)

## Summary

Make CI genuinely green. The shared rust-ci pin on `main` predates
standards#439, so the SHA-pinned `dtolnay/rust-toolchain` step errors
out before the job runs. This bumps the pin so rust-ci actually runs,
and brings the Rust sources to fmt + clippy(`-D warnings`) clean under
the CI toolchain (stable 1.96).

## Changes

- **rust-ci:** bump `rust-ci-reusable.yml` pin `d135b05` → `8dc2bf0`
(current `standards` HEAD; includes #439 toolchain fix + #441/#442).
- **Rust hygiene:** `cargo fmt` + `clippy --fix` where the repo had
pre-existing drift, so `cargo fmt --all -- --check` and `cargo clippy
--locked --all-targets -- -D warnings` pass.

## RSR Quality Checklist

### Required
- [x] Tests pass (`cargo test --locked --all-targets`)
- [x] Code is formatted (`cargo fmt --all -- --check`)
- [x] Linter is clean (`cargo clippy --locked --all-targets -- -D
warnings`)
- [x] No banned language patterns
- [x] SPDX license headers present on modified files
- [x] No secrets, credentials, or `.env` files included

## Testing

Verified locally with the CI toolchain (rustc/clippy/rustfmt 1.96.0):
`cargo fmt --check`, `clippy -D warnings`, `cargo check --locked`,
`cargo test --locked` all pass.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---
_Generated by [Claude
Code](https://claude.ai/code/session_01A6PSzJWpRxtzGDjUCEh7Mx)_

---------

Co-authored-by: Claude <noreply@anthropic.com>

Author: hyperpolymath

.github/workflows/rust-ci.yml

@@ -14,4 +14,4 @@ permissions:
 
 jobs:
   rust-ci:
-    uses: hyperpolymath/standards/.github/workflows/rust-ci-reusable.yml@d135b05bfc647d0c0fbfedc7e80f37ea50f49236
+    uses: hyperpolymath/standards/.github/workflows/rust-ci-reusable.yml@8dc2bf039d1ff0372d650895c46bea7fbaec68ff

tests/integration_tests.rs

@@ -345,7 +345,7 @@ fn test_full_free_skate_program_parsing_and_scoring() {
     );
 
     // Calculate total base value
-    let total_base: f64 = elements.iter().map(|e| scorer::base_value(e)).sum();
+    let total_base: f64 = elements.iter().map(scorer::base_value).sum();
     // Expected: 3Lz+3T(10.10) + 3F(5.30) + CCoSp4(3.50) + StSq3(3.30) +
     //           3Lo(4.90) + 2A+2T(4.60) + 3S(4.30) + FSSp3(2.50) +
     //           2A(3.30) + 3Lz+2T+2Lo(9.70) + CoSp4(3.00) + ChSq1(3.00)