feat(server): Extract crashpad annotations into contexts

[jan-auer]

Crashpad stores global and per-module annotations in the minidump. This PR
extracts these annotations into custom contexts to show them on the event.

Each module creates its own module with type crashpad and named after the
basename of the code file. The only exception are global annotations, which get
put into a context named crashpad.

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Example from Electron SDK:

[jan-auer]

cc @flub
cc @HazAT since this indirectly affects Electron.