feat(daemon): v2 privileged-write-channel daemon scaffold (phase 2)

docs/v2-protocol-contract-DESIGN.md

@@ -282,6 +282,23 @@ The CoR ordering (`SCHEMA_INVALID` → `ID_CONFLICT` → `TOMBSTONE_ORDER` → `
 
 The full testing pyramid (unit transport/validators → integration capability+handshake → contract error-taxonomy → scenario socket end-to-end) is therefore *specified by this contract*, not improvised in Phase 2.
 
+### 7.1 Phase 2 status (as built — PR #22)
+
+| Contract §7 item | Status |
+|---|---|
+| L1 framing (§4.1–4.3) + tests | ✅ `src/daemon/transport.ts`, 9 unit tests (round-trip, multibyte byte-count, oversize→BODY_TOO_LARGE encode+decode, partial-frame reassembly, coalesced, trailing-partial) |
+| JSON-RPC envelope (§4.2–4.3) | ✅ `src/daemon/jsonrpc.ts`, 12 unit tests |
+| Error taxonomy (§6) | ✅ `src/daemon/errors.ts` — full kind→code table; produced/asserted by the dispatch + scenario suites |
+| `hello` handshake (§4.4) | ✅ implemented as a normal verb; capability echoed |
+| Capability enforcement (§2.2) | ✅ per-verb gate + trust-cap, tested both capabilities incl. over the live socket |
+| **SO_PEERCRED resolver** | ⏭ **deferred to Phase 6.** Node exposes no public SO_PEERCRED API; faking it in the scaffold would be dishonest. Resolution is an injected Strategy seam (`DaemonOptions.resolveCapability`, DIP); the kernel-peer-uid resolver lands with the systemd/container topology where it belongs. Default = `operator` (trusted dev-mode, parent DESIGN §Dev-mode). |
+| L4 verbs → L3/core (§5) | ✅ full §5 surface wired except `area_stats` (needs MykbStore-internal db handle) and `rebuild` (CLI-inlined logic) → honestly UNSUPPORTED_OP via the CONTRACT_VERBS set, not faked |
+| **L2 StorageBackend Strategy contract suite** | ⏭ **deferred.** Parent DESIGN §L2 is explicit: "v2 day-1: LocalFsBackend only." The scaffold re-homes `src/core/*` directly (sanctioned re-homing, not rewriting); the reusable StorageBackend contract suite is extracted when a second backend (S3/NFS) is actually built (contract §8). |
+| Scenario e2e over real socket (capstone) | ✅ `tests/daemon/server.scenario.test.ts`, 4 scenario tests; representative verb of each group as operator + operator-only verb denied to agent over the wire + socket mode 0600 + split-write reassembly |
+| `supersede_entry` / envelope-v2 add-params | ⏭ wire-reserved per §3.1b/§8: `supersede_entry`→UNSUPPORTED_OP, `trust`/`validity`/`origin` accepted-but-not-persisted, until envelope-v2 phase 1 lands the schema. Trust-cap security check enforced now. |
+
+Pyramid as built: **53 daemon tests** — unit (transport 9 + jsonrpc 12) → integration (dispatch 17 + verbs 12) → scenario (server 4); full project sweep 634/634 green. The two ⏭ items are deferred *to a named later phase with a stated reason*, not skipped.
+
 ## 8. Deferred (explicitly not in this contract)
 
 - RBAC token model (§2.2) — additive `hello.params.token`, no protocol bump, build when a service-account curator needs sub-operator gating.

package.json

@@ -59,6 +59,7 @@
     "bundle:cli": "node scripts/bundle-cli.mjs",
     "bundle:all": "npm run bundle && npm run bundle:cli",
     "test": "vitest run",
+    "daemon:dev": "npm run build && node dist/daemon/main.js",
     "lint": "eslint . && prettier --check .",
     "clean": "rm -rf dist coverage",
     "prepublishOnly": "npm run clean && npm run build"

src/daemon/capability.ts

@@ -0,0 +1,20 @@
+/**
+ * Connection capability — `docs/v2-protocol-contract-DESIGN.md` §2.2.
+ *
+ * Derived by the daemon from the connecting peer's OS credentials
+ * (`SO_PEERCRED`) at accept time, NOT from anything the client asserts.
+ * The kernel attests the peer uid; the daemon does not trust a client's
+ * self-declared trust level beyond its connection capability. This is the
+ * single mechanism that both resolves the parent DESIGN's auth open-decision
+ * and closes the envelope-v2 trust-forgery hole (§3.1a).
+ *
+ *  - `operator`: peer uid owns the brain. May call maintenance verbs and
+ *    may assert `trust: 'operator'` on writes.
+ *  - `agent`: any other peer (the in-container Pi extension). Mutation +
+ *    read + workspace verbs only; any asserted trust is capped at `agent`.
+ */
+export type Capability = 'operator' | 'agent';
+
+export interface ConnContext {
+  capability: Capability;
+}