feat: Extract parsing to its own pass and do it in parallel

[sirasistant]

Description

Rework of #3849 after file_manager_with_stdlib was created. Also as @kevaundray suggested extracted the parsing above the context.

Resolves #3838

Problem*

Parsing is currently done when collecting, allowing only to parse files used, but making it very difficult to do parallel parsing or to have cached parsing.

Summary*

This PR extracts parsing to its own pass, and makes the Context take the parsed files. The creator of the context is the one in charge to do the parsing of the file manager, so Nargo, the LSP and wasm need to handle the parsed files. This PR uses rayon to do parallel parsing in Nargo & LSP. It reduces the time taken to process the on save notification in the LSP from ~700ms on protocol circuits to ~250ms.

With parsing being in its own pass, this opens the door for the LSP to cache parsing. It has access to the file manager and the parsed files, so it can detect which files have changed on disk and only parse those when necessary.

Additional Context

Documentation*

Check one:

• No documentation needed.
• Documentation included in this PR.
• [Exceptional Case] Documentation to be submitted in a separate PR.

PR Checklist*

• I have tested the changes locally.
• I have formatted the changes with Prettier and/or cargo fmt on default settings.

[kobyhallx]

LGTM 💯