feat: implement T14, T10 — enforcement middleware, LLDAP adapter

- T14: Unsupported feature registry with 7 pre-registered profile boundaries
- T10: LLDAP adapter implementing UserRepository; validator-gated reads

24 tests pass, go vet clean.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/go.mod

@@ -1,14 +1,19 @@
 module keycape
 
-go 1.22
+go 1.23.0
 
 require (
+	github.com/go-ldap/ldap/v3 v3.4.12
 	github.com/rs/zerolog v1.34.0
 	gopkg.in/yaml.v3 v3.0.1
 )
 
 require (
+	github.com/Azure/go-ntlmssp v0.0.0-20221128193559-754e69321358 // indirect
+	github.com/go-asn1-ber/asn1-ber v1.5.8-0.20250403174932-29230038a667 // indirect
+	github.com/google/uuid v1.6.0 // indirect
 	github.com/mattn/go-colorable v0.1.13 // indirect
 	github.com/mattn/go-isatty v0.0.19 // indirect
-	golang.org/x/sys v0.12.0 // indirect
+	golang.org/x/crypto v0.36.0 // indirect
+	golang.org/x/sys v0.31.0 // indirect
 )