### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current behaviour

I randomly encountered this by loading a wallet created from master with an older version. I could trace it down to bd13dc2f46ea10302a928fcf0f53b7aed77ad260 (#26076), but I don't know descriptor wallets enough to understand what's going on (cc @Sjors @achow101).

### Expected behaviour

`bitcoind` starts, or at least tells me to use a later version if #26076 was a breaking change instead of corrupting `wallet.dat`.

### Steps to reproduce

(master, clean chain): 
`createwallet -regtest ""`
(v25.0rc2):
first `bitcoind -regtest` succeeds
then stop and restart the node: The second `bitcoind -regtest` leads to an InitError:
`Error: Error: Unable to expand wallet descriptor from cache`
now, the wallet cannot be loaded by either version.

### Relevant log output

_No response_

### How did you obtain Bitcoin Core

Compiled from source

### What version of Bitcoin Core are you using?

v25.0rc2 / master

### Operating system and version

Ubuntu

### Machine specifications

_No response_
if (node) {
            if (ctx != ParseScriptContext::P2WSH) {
                error = "Miniscript expressions can only be used in wsh";
                return nullptr;
            }
            if (parser.m_key_parsing_error != "") {
                error = std::move(parser.m_key_parsing_error);
                return nullptr;
            }
            if (!node->IsSane()) {
                
                auto insane_node = node.get();
                if (const auto sub = node->FindInsaneSub()) insane_node = sub;
                if (const auto str = insane_node->ToString(parser)) error = *str;
                if (!insane_node->IsValid()) {
                    error += " is invalid";
                } else {
                    error += " is not sane";
                    if (!insane_node->IsNonMalleable()) {
                        error += ": malleable witnesses exist";
                    } else if (insane_node == node.get() && !insane_node->NeedsSignature()) {
                        error += ": witnesses without signature exist";
                    } else if (!insane_node->CheckTimeLocksMix()) {
                        error += ": contains mixes of timelocks expressed in blocks and seconds";
                    } else if (!insane_node->CheckDuplicateKey()) {
                        error += ": contains duplicate public keys";
                    } else if (!insane_node->ValidSatisfactions()) {
                        error += ": needs witnesses that may exceed resource limits";
                    }
                }