feat: add support for Postgres database provider (#79)

backend/go.mod

@@ -5,7 +5,6 @@ go 1.23.1
 require (
 	github.com/caarlos0/env/v11 v11.2.2
 	github.com/fxamacker/cbor/v2 v2.7.0
-	github.com/gin-contrib/cors v1.7.2
 	github.com/gin-gonic/gin v1.10.0
 	github.com/go-co-op/gocron/v2 v2.12.1
 	github.com/go-playground/validator/v10 v10.22.1
@@ -18,6 +17,7 @@ require (
 	github.com/oschwald/maxminddb-golang/v2 v2.0.0-beta.1
 	golang.org/x/crypto v0.27.0
 	golang.org/x/time v0.6.0
+	gorm.io/driver/postgres v1.5.11
 	gorm.io/driver/sqlite v1.5.6
 	gorm.io/gorm v1.25.12
 )
@@ -36,6 +36,10 @@ require (
 	github.com/google/go-tpm v0.9.1 // indirect
 	github.com/hashicorp/errwrap v1.1.0 // indirect
 	github.com/hashicorp/go-multierror v1.1.1 // indirect
+	github.com/jackc/pgpassfile v1.0.0 // indirect
+	github.com/jackc/pgservicefile v0.0.0-20221227161230-091c0ba34f0a // indirect
+	github.com/jackc/pgx/v5 v5.5.5 // indirect
+	github.com/jackc/puddle/v2 v2.2.1 // indirect
 	github.com/jinzhu/inflection v1.0.0 // indirect
 	github.com/jinzhu/now v1.1.5 // indirect
 	github.com/jonboulle/clockwork v0.4.0 // indirect
@@ -43,6 +47,7 @@ require (
 	github.com/klauspost/cpuid/v2 v2.2.8 // indirect
 	github.com/kr/pretty v0.3.1 // indirect
 	github.com/leodido/go-urn v1.4.0 // indirect
+	github.com/lib/pq v1.10.9 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/mattn/go-sqlite3 v1.14.23 // indirect
 	github.com/mitchellh/mapstructure v1.5.0 // indirect
@@ -57,6 +62,7 @@ require (
 	golang.org/x/arch v0.10.0 // indirect
 	golang.org/x/exp v0.0.0-20240909161429-701f63a606c0 // indirect
 	golang.org/x/net v0.29.0 // indirect
+	golang.org/x/sync v0.8.0 // indirect
 	golang.org/x/sys v0.25.0 // indirect
 	golang.org/x/text v0.18.0 // indirect
 	google.golang.org/protobuf v1.34.2 // indirect