Move some documentation to templates for easier updating

[nmdefries]

Checklist

Please:

• Make sure this PR is against "dev", not "main" (unless this is a release
  PR).
• Request a review from one of the current main reviewers:
  brookslogan, nmdefries.
• Makes sure to bump the version number in DESCRIPTION. Always increment
  the patch version number (the third number), unless you are making a
  release PR from dev to main, in which case increment the minor version
  number (the second number).
• Describe changes made in NEWS.md, making sure breaking changes
  (backwards-incompatible changes to the documented interface) are noted.
  Collect the changes under the next release number (e.g. if you are on
  1.7.2, then write your changes under the 1.8 heading).
• See DEVELOPMENT.md for more information on the development
  process.

Change explanations for reviewer

Move duplicated params and other doc text to template files in man-roxygen so it can be easily changed all at once.

Note: R/methods-epi_archive.R is not updated here due to potential conflicts with pending #431.

[dshemetov]

TIL templates. There are probably a bunch of places we could use this, but happy to introduce incrementally.

Some failing checks, but overall looks good.