build: run lychee to check intra-repo links in action

[reubeno]

We run in --offline mode to avoid network traffic originated by potentially untrusted content.

[github-actions]

Performance Benchmark Report

Benchmark name	Baseline (μs)	Test/PR (μs)	Delta (μs)	Delta %
expand_one_string	3.41 μs	3.40 μs	-0.00 μs	⚪ Unchanged
instantiate_shell	60.27 μs	60.08 μs	-0.19 μs	⚪ Unchanged
instantiate_shell_with_init_scripts	30504.71 μs	30578.08 μs	73.37 μs	⚪ Unchanged
parse_bash_completion	2739.17 μs	2763.31 μs	24.14 μs	🟠 +0.88%
parse_sample_script	4.14 μs	4.14 μs	-0.00 μs	⚪ Unchanged
run_echo_builtin_command	89.85 μs	89.89 μs	0.04 μs	⚪ Unchanged
run_one_builtin_command	108.80 μs	108.04 μs	-0.76 μs	⚪ Unchanged
run_one_external_command	2059.39 μs	2035.75 μs	-23.63 μs	🟢 -1.15%
run_one_external_command_directly	1007.85 μs	1006.80 μs	-1.05 μs	⚪ Unchanged

Code Coverage Report: Only Changed Files listed

Package	Base Coverage	New Coverage	Difference
brush-core/src/jobs.rs	🔴 42.42%	🔴 37.23%	🔴 -5.19%
brush-core/src/shell.rs	🟢 77.31%	🟢 77.73%	🟢 0.42%
brush-shell/src/main.rs	🟢 90.26%	🟢 90.91%	🟢 0.65%
Overall Coverage	🟢 73.76%	🟢 73.71%	🔴 -0.05%

Minimum allowed coverage is 70%, this run produced 73.71%