Story: Inline edit of params from experiments webview

[mattseddon]

We want to be able to edit params values inline within the experiments webview.

🐉s:

1. Parameters files can be TOML, JSON, YAML or Python files: https://dvc.org/doc/user-guide/glossary#parameter-dependency.
2. Data type of each parameter is currently unknown.

Note: Studio team has already been through a couple of iterations of this. Look at what they have done.

From initial designs:

[mattseddon]

One stepping stone to get us to this functionality would be to show the run/queue editor/title menu items whenever a params file is the active editor in the workspace:

[mattseddon]

Closing placeholder and we have implemented a very basic solution. Will come back to it when we are ready to implement.