User:Monkbot/task 18: cosmetic cs1 template cleanup

Monkbot task 18 is a WP:COSMETICBOT task to cleanup cs1|2 templates. It is authorized by Wikipedia:Bots/Requests for approval/Monkbot 18.

cs1|2 templates are transcluded in more than 4.7 million pages. Task 18 is constrained to the canonical list of cs1|2 templates and their more common redirects. Wrapper templates are not considered.

Task 18 does these things:

1. deletes empty known and unknown named parameters
2. deletes empty positional parameters
3. deletes or repairs parameters inside html comments
4. deletes non-contributing parameter/value pairs
5. hyphenates cs1|2 parameters when they are written using the to-be-deprecated all-run-together form
6. converts known language names assigned to |language= to their MediaWiki codes

This task strives to leave template style as it found it so does not change whitespace in and around template parameters. There is an exception to that whitespace rule: blank lines within vertically formatted cs1|2 templates are removed. Though executed by WP:AWB, this task does not perform AWB general fixes.

Task 18 operates only in mainspace. Any article that has {{bots|deny=monkbot 18}} shall be skipped. Additionally, task 18 maintains a list of articles that it will not edit. Contact the bot's operator to get an article added to the list.

Update 2020-12-15: A modified version of the bot (namespace restriction and empty positional parameter portions disabled) is created for use on templates that wrap the cs1|2 canonical templates. This version will be run manually only in template namespace and is identified as task 18a.

Update 2021-01-10: Because the bot depends on results from mw:Help:CirrusSearch to focus its work, an alternate form of the bot task (18b) has been created that focuses on templates that are not cs1|2 templates but are (in many but not all cases) wrapper templates that use a cs1|2 template. Task 18b runs separately from the main task 18.