EXPERIMENTAL: replace KV-scan consensus with Autobase sidecar engine

Cut over domain resolution to an Autobase apply-based sidecar fed by
claim/vote dual-writes from dnsPass. Remove the legacy full-KV scan
getConsensusState path and wire all reads through consensus-view.

- Add consensus-resolver, consensus-events, consensus-apply,
  consensus-autobase, and consensus-view modules
- Dual-append consensus events on claim/vote dnsPassAdd/Remove
- Bootstrap sidecar from existing KV entries; persist
  consensusAutobaseKey in network manifest
- Expose sidecar health via GET /api/consensus/status and metrics
- Add consensus-resolver and consensus-apply unit tests
- Expand RFC 0001 to Implemented; update CONSENSUS.md

Rollback: deploy prior release; KV data unchanged, sidecar rebuilds on
next startup.

plugin-sites/domain.consensus/index.js

@@ -146,6 +146,10 @@ async function handler(req, res) {
           totalVotes: metrics.totalVotes || 0,
           avgVotesPerDomain: metrics.avgVotesPerDomain || 0
         },
+        sidecar: metrics.sidecar || {
+          open: false,
+          bootstrapComplete: false
+        },
         activePeers: connectedPeers,
         timestamp: Date.now()
       });