feat(compress): move CCtx zstd parameter setter to Rust

Keep the C helper's ZSTD_checkCParams assertion at the call boundary while
moving its three field assignments into the existing repr(C) Rust CCtx
parameter module. The Rust leaf updates cParams and fParams, resets the
compression-level marker to NO_CLEVEL, and leaves unrelated CCtx state intact.

Test Plan:
- `cargo test --manifest-path rust/Cargo.toml --no-default-features --features compression set_zstd_params_updates_only_zstd_parameter_fields` -- passed
- `make -B -C lib -j2 lib` -- passed
- `make -C tests -j2 fuzzer` -- passed
- `tests/fuzzer -s4560 -t47 -i48 -v` -- passed
- required clippy trio, nightly fmt, post-format clippy trio, and `git diff --check` -- passed

lib/compress/zstd_compress.c

@@ -137,6 +137,8 @@ ZSTD_CCtx_params* ZSTD_rust_createCCtxParams(ZSTD_customMem customMem);
 size_t ZSTD_rust_freeCCtxParams(ZSTD_CCtx_params* params);
 size_t ZSTD_rust_CCtxParams_init_advanced(ZSTD_CCtx_params* cctxParams,
                                           ZSTD_parameters params);
+void ZSTD_rust_CCtxParams_setZstdParams(ZSTD_CCtx_params* cctxParams,
+                                        const ZSTD_parameters* params);
 int ZSTD_rust_useTargetCBlockSize(const ZSTD_CCtx_params* cctxParams);
 int ZSTD_rust_blockSplitterEnabled(ZSTD_CCtx_params* cctxParams);
 
@@ -711,12 +713,7 @@ static void ZSTD_CCtxParams_setZstdParams(
         ZSTD_CCtx_params* cctxParams, const ZSTD_parameters* params)
 {
     assert(!ZSTD_checkCParams(params->cParams));
-    cctxParams->cParams = params->cParams;
-    cctxParams->fParams = params->fParams;
-    /* Should not matter, as all cParams are presumed properly defined.
-     * But, set it for tracing anyway.
-     */
-    cctxParams->compressionLevel = ZSTD_NO_CLEVEL;
+    ZSTD_rust_CCtxParams_setZstdParams(cctxParams, params);
 }
 
 ZSTD_bounds ZSTD_cParam_getBounds(ZSTD_cParameter param)