fix(kms): re-tag go.sum for luxfi/age@v1.5.0 (second re-tagged dep)

After the keys@v1.1.0 go.sum fix (1889442), the Build KMS run for
v1.9.14 surfaced a SECOND re-tagged module at 'go mod download':
luxfi/age@v1.5.0 was force-moved the same way (the 'fa86744 vendor:
sync luxfi/keys + luxfi/age docs' lineage), so CI's direct-from-GitHub
fetch computed h1:zC/Fw/… while go.sum pinned the stale
h1:G69HbSV4… → checksum mismatch.

Updated the one age h1 line to the authoritative current hash
(verified from a pristine GOMODCACHE; the /go.mod hash was unchanged).
A full pristine 'go mod download' of the entire module graph (CI
fidelity: isolated cache, GOPROXY=direct, GOWORK=off) is now CLEAN —
no remaining checksum mismatches. age is not compiled into the
cmd/kms server binary (transitive verify-only dep).

go.sum

@@ -138,7 +138,7 @@ github.com/luxfi/accel v1.1.9 h1:Tsk6gXj2uKE19501bD0ajRYdeCHIlTGb6jYyLc+F8hc=
 github.com/luxfi/accel v1.1.9/go.mod h1:K00BcnLzEYMPHwCFq8Tf/450ApmTs9xBVvYOnofJCkc=
 github.com/luxfi/address v1.0.1 h1:Sc4keyuVzBIvHr7uVeYZf2/WY9YDGUgDi/iiWenj49g=
 github.com/luxfi/address v1.0.1/go.mod h1:5j3Eh66v9zvv1GbNdZwt+23krV8JlSDaRzmWZU8ZRM0=
-github.com/luxfi/age v1.5.0 h1:G69HbSV4R3vKEH9B0CulnRaMdSdf4RalMgP8xKmxHeI=
+github.com/luxfi/age v1.5.0 h1:zC/Fw/ptZwAXr9nqrxmrcf8752EIl1Lq9RECp9OmCO0=
 github.com/luxfi/age v1.5.0/go.mod h1:iAYAxgvrXxcy746+Ovh/eWWDuF9teJLNcCSSOX9RYW0=
 github.com/luxfi/cache v1.2.1 h1:kAzOS55/hmYeNKR+0HAKv4ma48Y6JjkI8UQeqdZ8bfI=
 github.com/luxfi/cache v1.2.1/go.mod h1:co7JTxZZHpKT31Yh01LFp5aZOxmoUg157FhBLQdQHVU=