feat: Add rule for unused function arguments (flowr)

[etiennebacher]

Just to explore

[codecov]

Codecov Report

❌ Patch coverage is 81.72691% with 91 lines in your changes missing coverage. Please review.
✅ Project coverage is 93.30%. Comparing base (9307d15) to head (4e766b0).
⚠️ Report is 6 commits behind head on flowr-dfg.

Files with missing lines	Patch %	Lines
.../src/lints/base/unused_argument/unused_argument.rs	71.87%	72 Missing ⚠️
crates/jarl-core/src/namespace.rs	36.66%	19 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##           flowr-dfg     #454      +/-   ##
=============================================
- Coverage      93.52%   93.30%   -0.23%     
=============================================
  Files            209      211       +2     
  Lines          25763    26257     +494     
=============================================
+ Hits           24096    24499     +403     
- Misses          1667     1758      +91     

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[github-actions]

Benchmark on real-projects

Repository	Avg. duration (main, seconds)	Avg. duration (PR, seconds)	PR - main	PR - main (%)	Number of iterations
easystats/datawizard	0.5826097	0.6159875	0.03337787	5.729028	50
lrberge/stringmagic	0.1423580	0.1752649	0.03290689	23.115585	50
pola-rs/r-polars	0.6458659	0.7483006	0.10243468	15.860054	50
Rdatatable/data.table	0.2012152	0.2949483	0.09373316	46.583544	50
ropensci/targets	0.7498389	0.8255069	0.07566804	10.091239	50
rstudio/shiny	0.5929183	0.6398422	0.04692393	7.914063	50
tidyverse/dplyr	0.6032027	0.6534377	0.05023492	8.328032	50
tidyverse/ggplot2	0.7363919	0.8116068	0.07521497	10.213986	50
vincentarelbundock/marginaleffects	0.5730362	0.6147321	0.04169595	7.276321	50
wch/r-source	1.3313834	1.8821720	0.55078860	41.369646	50