Refactor crypto package to use p256k1 signer

- Replaced the p256k package with p256k1.mleku.dev/signer across the codebase, updating all instances where the previous signer was utilized.
- Removed the deprecated p256k package, including all related files and tests, to streamline the codebase and improve maintainability.
- Updated various components, including event handling, database interactions, and protocol implementations, to ensure compatibility with the new signer interface.
- Enhanced tests to validate the new signing functionality and ensure robustness across the application.
- Bumped version to v0.23.3 to reflect these changes.

cmd/aggregator/main.go

@@ -17,7 +17,7 @@ import (
 
 	"lol.mleku.dev/chk"
 	"lol.mleku.dev/log"
-	"next.orly.dev/pkg/crypto/p256k"
+	p256k1signer "p256k1.mleku.dev/signer"
 	"next.orly.dev/pkg/crypto/sha256"
 	"next.orly.dev/pkg/encoders/bech32encoding"
 	"next.orly.dev/pkg/encoders/event"
@@ -335,7 +335,7 @@ func NewAggregator(keyInput string, since, until *timestamp.T, bloomFilterFile s
 		}
 
 		// Create signer from private key
-		signer = &p256k.Signer{}
+		signer = p256k1signer.NewP256K1Signer()
 		if err = signer.InitSec(secretBytes); chk.E(err) {
 			return nil, fmt.Errorf("failed to initialize signer: %w", err)
 		}