fix(review): gate the literal-glob source-context test to unix

The test writes a file literally named `[literal]*.rs` to prove the
glob-looking path is read literally. `*` cannot appear in a Windows
filename, so std::fs::write fails with InvalidFilename (OS error 123)
before any assertion runs — Test (windows-latest) failed twice on this
exact line (review_pr.rs:692).

Follows the adjacent source_context_never_follows_a_pinned_symlink
test, which is cfg(unix) for the same class of reason.

  source_context_is_bounded_line_exact_and_uses_literal_paths
    1 passed; 0 failed; finished in 0.21s

Signed-off-by: CodeWhale Bot <[email protected]>

crates/tui/src/tools/review_pr.rs

@@ -678,6 +678,9 @@ mod tests {
         assert!(bounded["repository_context"].is_null());
     }
 
+    // `*` cannot appear in a Windows filename, so the literal-glob path this
+    // guards is unrepresentable there.
+    #[cfg(unix)]
     #[test]
     fn source_context_is_bounded_line_exact_and_uses_literal_paths() {
         let dir = repository();