[DUX-1511] Error/warning replay

[9999years]

There's a few quality-of-life issues with errors and warnings.

Warnings are only printed once, so if the module isn't changed warnings won't be shown again. We could save warnings and print them out on each reload.

Similarly, errors can get buried under compilation output, so it could be useful to replay those as well.

We already parse compilation output, so this should be fairly easy to fix.

Note: If a file is compiled, then an error is introduced, and then the file is reverted back to its original form, it will be reloaded but no [n of m] Compiling ModuleName message will be printed; this means that we need some more sophisticated logic than just looking at compilation messages to determine when to clear diagnostics for a file.

_{From SyncLinear.com | DUX-1511}