Custom Linter rules without needing to maintain a build of bicep & it's editor extensions

**Is your feature request related to a problem? Please describe.**
A missing feature in realtime building / editing of bicep files is an easy mechanism that adds the ability to have personalised linter rules for both the cli and the extension to make use of. An example of other tooling where this has been added would be PSScriptAnalzyer

This would allow for team based rulesets that go above and beyond the ones natively provided.

**Describe the solution you'd like**

Simpler way to have custom rules without having to recompile bicep and the extensions to make use of these rules.

** Credit to @gsuttie for this [tweet](https://twitter.com/gregor_suttie/status/1659328362425229312) that reminded me of how this all works and how painful it is today to author, use and share custom rules without resorting to other tooling or out of editor feedback loops

The issue identifies the CLI and editor extensions as the integration points; begin by tracing how each currently applies built-in linter rules. Done means teams can provide shared custom rules consumed by both paths without maintaining a rebuilt Bicep compiler or editor extension.

Written by the indexing model from the issue text.