feat: print help when no subcommand is supplied

[bergzand]

This prints the common help output from clap when no ~~argument~~ subcommand is supplied. This does remove the single print statement showing the project root, relpath and project file.

Is there an actual use case for running laze without any subcommand?

[github-actions[bot]]

Bencher Report

Branch	pr/arg_required_else_help
Testbed	github-actions

Click to view all benchmark results

Benchmark	perf:task-clock	Benchmark Result msec x 1e3 (Result Δ%)	Upper Boundary msec x 1e3 (Limit %)
laze -C RIOT build --global --generate-only	📈 view plot 🚷 view threshold	8.93 x 1e3 (-3.70%) Baseline: 9.27 x 1e3	9.77 x 1e3 (91.39%)

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[kaspar030]

Is there an actual use case for running laze without any subcommand?

Printing the help is certainly better than the current state. I'd rather have some descriptive message, maybe even per-project. Let me think about this.

[bergzand]

Printing the help is certainly better than the current state. I'd rather have some descriptive message, maybe even per-project. Let me think about this.

Any suggestions on how to progress here?