Fixes https://github.com/coder/coder/issues/22375
Updates `stringutil.Truncate` to properly handle multi-byte UTF-8
characters.
Adds tests for multi-byte truncation with word boundary.
Created by Mux using Opus 4.6
Adds some extra meta data sent to provisioners. Also adds a field
`reuse_terraform_workspace` to tell the provisioner whether or not to
use the caching experiment.
- Adds a --name argument to provisionerd start
- Plumbs through name to integrated and external provisioners
- Defaults to hostname if not specified for external, hostname-N for integrated
- Adds cliutil.Hostname