[SMTChecker] Features that could be more precise

This issue tracks features that are currently implemented in the SMTChecker in some form, but could be more precise:

- [x] erase knowledge only about assigned index https://github.com/ethereum/solidity/issues/6178
- [ ] variables of FunctionType https://github.com/ethereum/solidity/issues/8330
- [ ] memory/storage pointers https://github.com/ethereum/solidity/issues/9148
- [ ] some inline assembly https://github.com/ethereum/solidity/issues/10596

Start with the SMTChecker context and review linked issues 8330, 9148, and 10596, since this issue only tracks broader precision gaps. Done would require addressing one of those listed areas, but the issue does not identify a file, test, or specific implementation scope.

Written by the indexing model from the issue text.