feat: ship cadical

[Kha]

[Kha]

Let's first see if it builds at all

[leanprover-community-mathlib4-bot]

Mathlib CI status (docs):

• ✅ Mathlib branch lean-pr-testing-4325 has successfully built against this PR. (2024-06-11 14:53:46) View Log
• ❗ Batteries CI can not be attempted yet, as the nightly-testing-2024-08-19 tag does not exist there yet. We will retry when you push more commits. If you rebase your branch onto nightly-with-mathlib, Batteries CI should run now. (2024-08-19 08:46:04)
• 🟡 Mathlib branch lean-pr-testing-4325 build against this PR was cancelled. (2024-08-20 16:03:21) View Log
• 🟡 Mathlib branch lean-pr-testing-4325 build against this PR was cancelled. (2024-08-21 17:50:51) View Log
• 🟡 Mathlib branch lean-pr-testing-4325 build against this PR was cancelled. (2024-08-21 23:50:47) View Log
• 🟡 Mathlib branch lean-pr-testing-4325 build against this PR was cancelled. (2024-08-22 22:47:09) View Log
• 🟡 Mathlib branch lean-pr-testing-4325 build against this PR was cancelled. (2024-08-23 15:16:05) View Log