fix(server): fix numeric comparisons for float custom tags in smart playlists (#4116)

* Fix numeric comparisons for custom float tags

* feat(criteria): cast numeric tags for sorting and comparisons

Signed-off-by: Deluan <deluan@navidrome.org>

---------

Signed-off-by: Deluan <deluan@navidrome.org>

model/criteria/operators_test.go

@@ -13,6 +13,7 @@ import (
 var _ = BeforeSuite(func() {
 	AddRoles([]string{"artist", "composer"})
 	AddTagNames([]string{"genre"})
+	AddNumericTags([]string{"rate"})
 })
 
 var _ = Describe("Operators", func() {
@@ -68,6 +69,15 @@ var _ = Describe("Operators", func() {
 		Entry("role endsWith [string]", EndsWith{"composer": "Lennon"}, "exists (select 1 from json_tree(participants, '$.composer') where key='name' and value LIKE ?)", "%Lennon"),
 	)
 
+	// TODO Validate operators that are not valid for each field type.
+	XDescribeTable("ToSQL - Invalid Operators",
+		func(op Expression, expectedError string) {
+			_, _, err := op.ToSql()
+			gomega.Expect(err).To(gomega.MatchError(expectedError))
+		},
+		Entry("numeric tag contains", Contains{"rate": 5}, "numeric tag 'rate' cannot be used with Contains operator"),
+	)
+
 	Describe("Custom Tags", func() {
 		It("generates valid SQL", func() {
 			AddTagNames([]string{"mood"})
@@ -77,6 +87,14 @@ var _ = Describe("Operators", func() {
 			gomega.Expect(sql).To(gomega.Equal("exists (select 1 from json_tree(tags, '$.mood') where key='value' and value LIKE ?)"))
 			gomega.Expect(args).To(gomega.HaveExactElements("%Soft"))
 		})
+		It("casts numeric comparisons", func() {
+			AddNumericTags([]string{"rate"})
+			op := Lt{"rate": 6}
+			sql, args, err := op.ToSql()
+			gomega.Expect(err).ToNot(gomega.HaveOccurred())
+			gomega.Expect(sql).To(gomega.Equal("exists (select 1 from json_tree(tags, '$.rate') where key='value' and CAST(value AS REAL) < ?)"))
+			gomega.Expect(args).To(gomega.HaveExactElements(6))
+		})
 		It("skips unknown tag names", func() {
 			op := EndsWith{"unknown": "value"}
 			sql, args, _ := op.ToSql()