* feat: influence parameter defaults through cli flag/env
Add a --parameter-default flag / CODER_RICH_PARAMETER_DEFAULT
environment variable which overrides default values suggested for
parameters.
This allows scripts or middleware wrapping the CLI to substitute
defaults for parameter values beyond those defined at the template
level. For example, Git repository/branch parameters can be given
defaults based on the current checkout, or default parameter values can
be parsed out of files inside the repo.
* Rename defaults arg to defaultOverrides
This change will improve over CLI performance and "snappiness" as well as
substantially reduce our test times. Preliminary benchmarks show
`coder server --help` times cut from 300ms to 120ms on my dogfood
instance.
The inefficiency of lipgloss disproportionately impacts our system, as all help
text for every command is generated whenever any command is invoked.
The `pretty` API could clean up a lot of the code (e.g., by replacing
complex string concatenations with Printf), but this commit is too
expansive as is so that work will be done in a follow up.
