Implement the spec's ranking and recommendation heuristic:
1. Highest unique discovered node count
2. Highest neighbor-report diversity (direct + mesh)
3. Highest non-duplicate packet count
4. Best median link quality (SNR first, then RSSI)
5. Greatest best known distance
6. Lowest failure/reconnect penalty
Presets tied after all 6 criteria share the same rank with isTied=true.
Includes RankingScoreBreakdown for transparent per-criterion scoring.
11 unit tests covering each criterion as tiebreaker, full ties,
edge cases (empty/single preset, no nodes, failed presets).
Validated: spotlessApply, allTests, kmpSmokeCompile
- Add Preparing, Cancelling, Failed states to DiscoveryScanState (FR-008)
- Change Complete to data class with CompletionOutcome enum
- Add local-mesh-discovery deep link routes to DeepLinkRouter (FR-031)
- Compute packetSuccessRate/packetFailureRate in scan engine (FR-012)
- Fix DiscoveryScanEngineTest compilation and restructure with shared scheduler
- All 8 tests pass, kmpSmokeCompile clean
