[feat] add support for `pre` and `post` scripts

[nickfrosty]

when performing common tasks with the anchor CLI (like building a program), it would improve devex if the cli support pre and post commands. this idea already exists in the npm world (see npm docs here)

recommend support generic pre and post prefixes on any of the Anchor.toml scripts to enable devs to not have to manually run additional commands after completion of various tasks: they can be run automatically

example use case generate a Codama client:

• Anchor.toml has a prebuild script declared that runs the Codama CLI to generate the JS/Rust client
• a dev runs anchor build:
  1. the anchor cli should checks for prebuild => if found, run it
  2. the anchor cli executes the normal build logic
  3. the anchor cli should checks for postbuild => if found, run it

[Aursen]

A first attempt here: #1796