Bootstrap copied BFF and local accounts with public Sendico contracts (#34)

backend/pkg/db/repository/builder/pipeline.go

@@ -0,0 +1,24 @@
+package builder
+
+import (
+	"git.sendico.io/tech/sxchnge/bff/pkg/mservice"
+	"go.mongodb.org/mongo-driver/v2/mongo"
+)
+
+type Pipeline interface {
+	Match(filter Query) Pipeline
+	Lookup(from mservice.Type, localField, foreignField, as Field) Pipeline
+	LookupWithPipeline(
+		from mservice.Type,
+		pipeline Pipeline, // your nested pipeline
+		as Field,
+		let *map[string]Field, //  optional e.g. {"projRef": Field("$_id")}
+	) Pipeline
+	// unwind with functional options
+	Unwind(path Field, opts ...UnwindOption) Pipeline
+	Count(field Field) Pipeline
+	Group(groupBy Alias, accumulators ...GroupAccumulator) Pipeline
+	Project(projections ...Projection) Pipeline
+	ReplaceRoot(newRoot Expression) Pipeline
+	Build() mongo.Pipeline
+}