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.

pkg/database/query-events-search_test.go

@@ -7,7 +7,7 @@ import (
 	"time"
 
 	"lol.mleku.dev/chk"
-	"next.orly.dev/pkg/crypto/p256k"
+	p256k1signer "p256k1.mleku.dev/signer"
 	"next.orly.dev/pkg/encoders/event"
 	"next.orly.dev/pkg/encoders/filter"
 	"next.orly.dev/pkg/encoders/kind"
@@ -44,7 +44,7 @@ func TestQueryEventsBySearchTerms(t *testing.T) {
 	}()
 
 	// signer for all events
-	sign := new(p256k.Signer)
+	sign := p256k1signer.NewP256K1Signer()
 	if err := sign.Generate(); chk.E(err) {
 		t.Fatalf("signer generate: %v", err)
 	}