feat(rust): port optimal binary-tree updates

Move the binary-tree table maintenance shared by optimal compression strategies
into Rust. A small C projection preserves the private match-state boundary;
the dynamic-programming parser and match selection remain C-owned for now.

The Rust implementation covers prefix and external-dictionary tree updates and
preserves the optional C predictor path. The component map now distinguishes
this migrated tree layer from the remaining optimal parser.

Test Plan:
- cargo test --all-targets
- cargo test --target i686-unknown-linux-gnu --all-targets
- cargo clippy && cargo clippy --benches && cargo clippy --tests
- cargo +nightly fmt
- make -B -C tests -j2 fuzzer zstreamtest invalidDictionaries
- ./tests/fuzzer -s5346 -i1 --no-big-tests
- ./tests/zstreamtest -i3000 -s334462
- ./tests/invalidDictionaries
- make -B -C tests fuzzer32 MOREFLAGS=-DZSTD_C_PREDICT
- ./tests/fuzzer32 -s5346 -i1 --no-big-tests
- byte-compare C and Rust-control CLI output at levels 13, 16, 19, and 22
  for random, patterned, zero, and dictionary inputs with and without
  ZSTD_C_PREDICT

Refs: rust/README.md

rust/README.md

@@ -35,6 +35,8 @@ zstd ABI:
     fast block match finders, including attached and external dictionary paths.
   - `zstd_lazy` implements greedy, lazy, lazy2, and binary-tree matching,
     including row-based and dictionary search variants.
+  - `zstd_opt_tree` maintains the binary-tree index used by optimal matching;
+    the dynamic-programming optimal parser itself remains in C for now.
 - Runtime support
   - `threading` provides platform pthread wrappers required by zstd headers.
   - `pool` implements the bounded worker pool used by multithreaded compression.