Refactor signer implementation to use p8k package

- Replaced all instances of p256k1signer with the new p8k.Signer across various modules, including event creation, policy handling, and database interactions.
- Updated related test cases and benchmarks to ensure compatibility with the new signer interface.
- Bumped version to v0.25.0 to reflect these significant changes and improvements in cryptographic operations.

pkg/crypto/p8k/bench/go.mod

@@ -0,0 +1,25 @@
+module bench
+
+go 1.25.3
+
+require (
+	github.com/btcsuite/btcd/btcec/v2 v2.3.6
+	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.3.0
+	p256k1.mleku.dev v1.0.2
+	p8k.mleku.dev v0.0.0
+	p8k.mleku.dev/p8k v0.0.0-00010101000000-000000000000
+)
+
+require (
+	github.com/btcsuite/btcd/chaincfg/chainhash v1.1.0 // indirect
+	github.com/decred/dcrd/crypto/blake256 v1.1.0 // indirect
+	github.com/ebitengine/purego v0.9.1 // indirect
+	github.com/klauspost/cpuid/v2 v2.3.0 // indirect
+	github.com/minio/sha256-simd v1.0.1 // indirect
+	golang.org/x/sys v0.37.0 // indirect
+)
+
+replace (
+	p8k.mleku.dev => ../
+	p8k.mleku.dev/p8k => ../p8k
+)