### What?
If you had multiple operator constraints on a single field, the last one
defined would be the only one used.
Example:
```ts
where: {
id: {
in: [doc2.id],
not_in: [], // <-- only respected this operator constraint
},
}
```
and
```ts
where: {
id: {
not_in: [],
in: [doc2.id], // <-- only respected this operator constraint
},
}
```
They would yield different results.
### Why?
The results were not merged into an `$and` query inside parseParams.
### How?
Merges the results within an `$and` constraint.
Fixes https://github.com/payloadcms/payload/issues/10944
Supersedes https://github.com/payloadcms/payload/pull/11011