v0.63.0: B3+B2 fresh-install fixes — TokenStore reload-on-miss + guesthook snippets dir

B3: Lookup re-reads the append-only store once on a miss (cross-process
coherence with the one-shot provisioner; size short-circuit bounds the cost;
behind the TokenAuthority seam). B2: fenced mkdir -p /var/lib/vz/snippets
before the snippet install + the one narrow sudoers grant. Both red-proofed;
drill findings DRILL-day0-cleanroom-2026-07-03 B3/B2.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PSK5g6qYLknKj8u3QAFEr6

cmd/felhom-agent/main.go

@@ -45,7 +45,7 @@ import (
 
 // version is the agent version. Overridable at build time with
 // -ldflags "-X main.version=<v>"; defaults to the in-repo CHANGELOG version.
-var version = "0.62.0"
+var version = "0.63.0"
 
 // runGuestHook is the PVE pre-start hook body (`felhom-agent guest-hook <vmid> <phase>`). On the
 // pre-start phase it creates placeholder dirs for any absent bind-mount source so the guest always boots