Add `llms.txt` to docs

Added

• llms.txt to docs
• Elixir 1.19 to CI
• OTP 28.5 to CI

Changed

• CI from Ubuntu 20.04 to 22.04
• oldest supported Elixir version from 1.7 to 1.11
• oldest supported OTP version from 21 to 24

Fix compilation warning on Elixir 1.18

Added

• latest blocklist tweaks

Fixed

• compilation warning on Elixir 1.18

0.2.0

Added

• Elixir 1.17 to CI
• OTP 27.1 to CI

Changed

• [BREAKING] in supervised Sqids, if you had some non-default options declared
  but only the module's name defined as the supervisor child (as was
  recommended by docs), the options wouldn't work. Sqids now raises if this
  situation is detected to nudge users towards fixing it in the way that's best
  for each individual.

Fixed

• documentation on supervised Sqids: intended options were not passed
• compilation warnings on Elixir 1.17

0.1.3

Fixed

• decoding exception when ExUnit wasn't imported by caller (thanks to @tshakah)
• typos in README (thanks to @hanifanazka)

0.1.2

Added

• workaround for Dialyzer warnings when placing context in module attribute
• oldest sqids version in which each function, type and callback is available

Fixed

• Dialyzer warnings for suggestion of sqids context under module attribute

0.1.1

Added

• new!/0 and new!/1 to ease storing context in module attributes

Fixed

• unwarranted risk of new future warnings breaking the builds of sqids dependents

0.1.0

Added

• Elixir implementation of Sqids