Suport findAndRerank on a collection with vector / vectorize but without lexical index.

[amorton]

A findAndRerank query that does not explicitly ask for a lexical leg should succeed so long as the collection has a vector.

Examples of queries that should work without a lexcial index, but currently fail:

[
	{
		"findAndRerank": {
			"filter": {
			},
			"projection": {
			},
			"sort": {
				"$hybrid": "I like cheese!"
			},
			"options": {
				"limit": 10,
			}
		}
	},
{
		"findAndRerank": {
			"filter": {
			},
			"projection": {
				"_id": 1,
				"$vectorize": 1
			},
			"sort": {
				"$hybrid": {
					"$vectorize": "0-dimensional biomaterials lack inductive properties."
                                 }
			},
			"options": {
				"limit": 20,
				"includeScores": false,
				"includeSortVector": false
			}
		}
	},
	{
		"findAndRerank": {
			"filter": {
			},
			"projection": {
				"_id": 1,
				"name": 1,
				"$vectorize": 1
			},
			"sort": {
				"$hybrid": {
					"$vector": [
						0.030776024
					]
				}
			},
			"options": {
				"rerankQuery": "I like cheese",
				"rerankOn": "content",
				
				"limit": 10,
				"hybridLimits": {
					"$lexical": 15,
					"$vector": 35
				},
				"includeScores": true,
				"includeSortVector": false
			}
		}
	}
]

In the above, non of the explicitly as for a lexical sort.

NOTE: the $lexical in hybridLimits should be ignored if the sort does not ask for a lexical.

below is the user explicitly asking for a lexical sort, this should Fail if the collection does not have an index:

	{
		"findAndRerank": {
			"filter": {
			},
			"projection": {
				"_id": 1,
				"$vectorize": 1
			},
			"sort": {
				"$hybrid": {
					"$vectorize": "0-dimensional biomaterials lack inductive properties.",
					"$lexical": "tissue"
				}
			},
			"options": {
				"limit": 20,
				"includeScores": false,
				"includeSortVector": false
			}
		}
	}