[clang] [clang][analyzer] Add "pedantic" mode to StreamChecker. (PR #87322)

[Balázs Kéri via cfe-commits]

balazske wrote:

> Unless you plan to add more heuristics, I'd prefer a more concrete option name, like AssumeSuccessfulWrites=true. This would better describe it imo.

I do not like totally the name "Pedantic", it could be "AssumeOftenUncheckedOperationsMayFail". I am not sure if this behavior is needed only on write operations, the intent was to remove failure branches from all operations that are often unchecked.

https://github.com/llvm/llvm-project/pull/87322