05c450147c
New internal/reconcile package: the agent-side control core's structural half. - Per-guest serializer Queue (doc 03 §10): the single choke point all mutation sources funnel through; same-vmid serial in submit order, different vmids parallel (cond-var FIFO lanes). - Desired-state model + DesiredProvider seam; EmptyProvider is the only live source at slice 4 (no hub serving until slice 10) so the live engine computes an empty action set and performs zero mutations. - Normalization layer (FieldNormalizers): normalized desired-vs-actual so Proxmox round-trip quirks don't read as drift. normDesc promoted out of main.go to reconcile.NormDescription; selftest uses the shared helper. - Plan (pure diff): minimal benign action set (Start/Stop/SetConfig) for guests in both desired and actual; provision/destroy out of scope here. - Engine: dispatches onto the shared queue; honors the dual-mode SetConfig contract (UPID -> WaitTask; empty UPID -> synchronous success). - Durable op journal + idempotency store (mirrors authz.FileNonceStore): in-flight task ids for crash detection + AlreadyApplied dedupe across restart. - Wired into runDaemon alongside the hub loop, sharing the queue; runs cleanly with no desired state and no signers. Full module race-clean and vet-clean on the Linux build server. CHECKPOINT: Phase A only. Awaiting validation before Phase B (the reversibility gate + signed-op consuming layer, landing v0.4.0). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>