Draft: Add backtraces to all exceptions (#18159) - 2nd attempt

This supersedes: !3236 (closed)

Proposal

Submodules / Libraries

• https://gitlab.haskell.org/supersven/Cabal/-/tree/wip/ghc-exception-stacktraces-reduced
• https://gitlab.haskell.org/supersven/exceptions/-/tree/wip/ghc-exception-stacktraces
• https://gitlab.haskell.org/supersven/haskeline/-/tree/wip/ghc-exception-stacktraces
• https://gitlab.haskell.org/supersven/haddock/-/tree/wip/ghc-exception-stacktraces

Open Tasks

• Pretty printing of backtraces
• Adjust / add Haddock (especially, add the changes from the proposal.)
• General clean up (Formatting, remove left-overs, etc.)
• Figure out how to upstream changes on submodules. (That's mostly a chicken-and-egg problem.)

I.e. the implementation of the core functionality - as described by the proposal - is done. But, to finally merge it, the open issues should be resolved.