[llvm-branch-commits] [analyzer] Harden safeguards for Z3 query times (PR #95129)

[Balazs Benics via llvm-branch-commits]

https://github.com/steakhal created https://github.com/llvm/llvm-project/pull/95129

This patch is a functional change.
https://discourse.llvm.org/t/analyzer-rfc-taming-z3-query-times/79520

As a result of this patch, individual Z3 queries in refutation will be
bound by 300ms. Every report equivalence class will be processed in
at most 1 second.

The heuristic should have only really marginal observable impact -
except for the cases when we had big report eqclasses with long-running
(15s) Z3 queries, where previously CSA effectively halted.
After this patch, CSA will tackle such extreme cases as well.