Add sqlite backend

go.mod

@@ -5,7 +5,9 @@ go 1.24.1
 require (
 	fiatjaf.com/nostr v0.0.0-20250924142401-59bd3c29fffd
 	github.com/BurntSushi/toml v1.5.0
+	github.com/mattn/go-sqlite3 v1.14.32
 	github.com/spf13/afero v1.15.0
+	github.com/stretchr/testify v1.10.0
 )
 
 require (
@@ -16,6 +18,7 @@ require (
 	github.com/btcsuite/btcd/btcec/v2 v2.3.4 // indirect
 	github.com/btcsuite/btcd/chaincfg/chainhash v1.1.0 // indirect
 	github.com/coder/websocket v1.8.13 // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/decred/dcrd/crypto/blake256 v1.1.0 // indirect
 	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.4.0 // indirect
 	github.com/fasthttp/websocket v1.5.12 // indirect
@@ -26,6 +29,7 @@ require (
 	github.com/mailru/easyjson v0.9.0 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/puzpuzpuz/xsync/v3 v3.5.1 // indirect
 	github.com/rs/cors v1.11.1 // indirect
 	github.com/savsgio/gotils v0.0.0-20240704082632-aef3928b8a38 // indirect
@@ -37,4 +41,5 @@ require (
 	golang.org/x/exp v0.0.0-20250305212735-054e65f0b394 // indirect
 	golang.org/x/net v0.41.0 // indirect
 	golang.org/x/text v0.28.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 )