fix: workarounds for edge word parsing cases

[reubeno]

• Fixes 'Binary string matching with expansion' test case
• Adds + fixes 'Command substitution with embedded parens' test case

[github-actions]

Test Results

  2 files    9 suites   55s ⏱️
441 tests 441 ✅ 0 💤 0 ❌
876 runs  876 ✅ 0 💤 0 ❌

Results for commit 41a2d2e.

[github-actions]

Performance Benchmark Report

Benchmark name	Baseline (μs)	Test/PR (μs)	Delta (μs)	Delta %
expand_one_string	3.33 μs	3.33 μs	0.00 μs	⚪ Unchanged
instantiate_shell	60.45 μs	59.85 μs	-0.60 μs	⚪ Unchanged
instantiate_shell_with_init_scripts	28686.28 μs	28646.71 μs	-39.57 μs	⚪ Unchanged
parse_bash_completion	2712.21 μs	2692.57 μs	-19.64 μs	⚪ Unchanged
parse_sample_script	4.07 μs	4.01 μs	-0.06 μs	⚪ Unchanged
run_echo_builtin_command	90.79 μs	91.07 μs	0.28 μs	⚪ Unchanged
run_one_builtin_command	108.65 μs	108.90 μs	0.25 μs	⚪ Unchanged
run_one_external_command	2048.63 μs	1897.67 μs	-150.95 μs	🟢 -7.37%
run_one_external_command_directly	1008.11 μs	1006.86 μs	-1.25 μs	⚪ Unchanged

Code Coverage Report: Only Changed Files listed

Package	Base Coverage	New Coverage	Difference
brush-core/src/patterns.rs	🟢 96.98%	🟢 97.14%	🟢 0.16%
brush-interactive/src/reedline/reedline_shell.rs	🟢 89.84%	🟢 89.68%	🔴 -0.16%
Overall Coverage	🟢 71.98%	🟢 72.06%	🟢 0.08%

Minimum allowed coverage is 70%, this run produced 72.06%