Pair scoring evaluation - going through each pair in order

Requirements extracted:
- REQ-ARCH-1: "Many small acyclically-layered crates"
- REQ-ARCH-2: "Public SDK surface is spt-proto, spt-runtime, spt-msg"
- REQ-ARCH-3: "Wire-protocol version independent of crate semver"
- REQ-BRAIN-RESUME-NO-CONN-DEADLOCK: Daemon brain deadlock fix
- REQ-CI-WINDOWS-PHASE-A-BOUND: Windows nextest parallelism bound
- REQ-DIGEST-CROSS-NODE-PULL: Digest snapshot pull crosses nodes
- REQ-DOCS-4: "Agent-consumable layer (llms.txt, manifest schema, MCP, CLI help)"
- REQ-DOCS-RELEASE-ASSET: Docs bundle shipped as release asset
- REQ-EFFECTIVE-INSTANCE-STATE: Effective instance state derivation
- REQ-HAZARD-ADAPTER-APPLY-SILENT-NOOP: Delegated live adapter apply
- REQ-HAZARD-CASCADE-WIPE-GUARD: "No hard-delete of parent with non-empty children"
- REQ-HAZARD-COMMUNE-INGEST-BLACKHOLE: Commune/signoff ingest data-loss prevention
- REQ-HAZARD-CONPTY-DSR: "ConPTY reader must auto-answer DSR"
- REQ-HAZARD-DEFERRED-DRAIN: "Deferred spool rows excluded from event-stream drain"
- REQ-HAZARD-DEFERRED-SURVIVE-DRAIN: "Deferred rows survive poll drain"
- REQ-HAZARD-DRIVEN-BY-IDLE-REMOTE-EVICT: Remote controller eviction
- REQ-HAZARD-ECHO-BEFORE-SIGNOFF: "Echo-commune fires before INIT_SIGNOFF"
- REQ-HAZARD-ENVELOPE-PARSER-SAFE: "Two-slice envelope parser is panic-free"
- REQ-HAZARD-EPHEMERAL-CLEANUP: "Ephemeral perch cleanup on every ring exit"
- REQ-HAZARD-GRACE-BEFORE-SIGNOFF: "Grace-period wait before INIT_SIGNOFF"
- REQ-HAZARD-HANDOFF-ARGV-COMPAT: "Broker/brain IPC + handoff argv version-tolerant"
- REQ-HAZARD-PARENT-PID-PREFER: "Prefer stable parent PID over ephemeral"
- REQ-HAZARD-REGISTRY-DIR-CREATE: "SQLite store creates parent dir"
- REQ-HAZARD-SOFT-CLEANUP: "Soft-cleanup preserves state, removes ready marker"
- REQ-HOST-RUN-1: spt-hosted harness bringup
- REQ-NOTIF-SEAM-DISMISS: "Staleness dismissed at the seam"
- REQ-OPID-TRACING-RETRY: "Tracing-only op families auto-retry once"
- REQ-PAIR-NTP-LOUD-FAIL: "Total NTP failure is loud, not silent"
- REQ-PICKER-NODE-GROUPING: Bug #13 - picker shows machine once per subnet
- REQ-REDISPATCH-FINISHED-RETIRE: "Finished/terminal streams retired from redispatch"
- REQ-RUN-PICKER: "Interactive spt endpoint run picker (ratatui TUI)"
- REQ-SESSION-RESUME-TEMPLATE: Resuming endpoint session with conversation history
- REQ-STORE-1: "spt-store BranchStore (git branch as versioned KV)"
- REQ-TRANSLATE-COMMIT-MISS-TOLERANCE: "Commit miss is NOT a fault; preserve binary"
- REQ-WAKE-WAIT: "spt endpoint wake --wait blocks on real bind"