Rename the package and transfar the repo

[eitsupi]

Related to PRQL/prql#4081

• package name: prqlr -> prqlc
• repo name: eitsupi/prqlr -> PRQL/prqlc-r (?)

@max-sixty When transferring this repository to the PRQL organization, should the repository name be prqlc-r or r-prqlc? (Example of r- pattern: r-polars, example of -r pattern: duckdb-r)