[turbopack] Handle negative numbers as constants in the analyzer (#94218)
Previously, these were unknown / unsupported expressions:
```
Unknown {
original_value: None,
reason: "unsupported expression",
has_side_effects: true,
},
```
This prevented us from folding `-1 === -1` into true, for example. Most
of this PR's changes are updates to the snapshot. It exists in this
stack because the code it touches was moved in the stack.