Refer to canonical pacakge in case of duplicates

[krlmlr]

This also deals with the case where two packages import from a third package, and a fourth package overwrites it.

Will add tests.

Closes #93.

Example

library(conflicted)
library(plyr)
library(dm)
library(mcmcdata)

mutate
#> Error:
#> ! [conflicted] mutate found in 2 packages.
#> Either pick the one you want with `::`:
#> • dplyr::mutate
#> • plyr::mutate
#> Or declare a preference with `conflicts_prefer()`:
#> • `conflicts_prefer(dplyr::mutate)`
#> • `conflicts_prefer(plyr::mutate)`
#> Backtrace:
#>     ▆
#>  1. └─conflicted (local) `<fn>`()
#>  2.   └─cli::cli_abort(...) at conflicted/R/disambiguate.R:51:4
#>  3.     └─rlang::abort(...)

^{Created on 2023-09-26 with reprex v2.0.2}

[krlmlr]

Seeing weird behavior, will update:

conflicted::conflict_scout(c("devtools", "remotes"))
#> Error: bad namespace name

^{Created on 2023-09-26 with reprex v2.0.2}

[krlmlr]

Thanks for the guidance, it was very helpful!