feat: POSIX/P2P roadmap — multisig shape, socket bridge, bin index, docs

- Unify pear.multisig.json validation via bare-os-protocol + kernel boot fragment
- Socket bridge: SCM_RIGHTS path, ancillary handling, TCP half-close/shutdown how,
  connect tcpRecvQueue + poll/recv EOF and EPIPE-shaped errors
- Bin manifest / Hyperbee hints schema 2 + namesDigest; batch-write invalidation
- Host booter structured logging; BOOT_PERF_DETAIL bare_stdlib_merge_ns timing
- Wasm kernel optional syscall imports; security_posture rotation hints schema 2
- Shell errexit inside compound bodies; expand getconf/_SC_* and bareOsGetconfSysconf
- Subprocess bridge snapshot timeoutPolicy; blind-relay protomux backpressure tests
- Pear updater minimal delegate example + verify-pear scan; holepunch drift repos
- Refresh handbook, kernel-image, syscall-socket-contract, posix matrix, PEAR-RUN

Rebuild coreutils/bundles; bundle kernel; keep seeder/kernel parity.

kernel/README.md

@@ -37,6 +37,8 @@ Files in this directory are **read from disk by the seeder** (or copied into `pa
 3. Run `npm run build -w bare-os-bare-libs` when **`packages/bare-os-booter/lib/bare-module-manifest.json`** or bundle entries change.
 4. Run seeder again to re-stage the drive (or use a fresh Corestore for a clean image).
 
+**Host boot perf:** when **`BARE_OS_BOOT_PERF_DETAIL=1`**, the stock booter logs **`bare_stdlib_merge_ns`** after **`maybeMergeBareFromDrive`** (monotonic **`hrtime`** delta in nanoseconds) alongside guest **`boot-perf.json`** stages.
+
 Pear bundles use the **vendored** tree under `packages/bare-os-seeder/kernel/`; keep it in sync by running the same builds before `pear stage`. **`npm test`** runs **`scripts/verify-kernel-seeder-parity.mjs`**, **`scripts/verify-ctx-api-feature-bits.mjs`**, and **`scripts/validate-example-schemas.mjs`** (after **`bare-os-coreutils`** and **`bare-os-bare-libs`** builds) so the two trees match byte-for-byte, ctx semver / feature words stay wired, example JSON matches **[`docs/schemas/`](../docs/schemas/)**, and every **`kernel/bin/*`** file contains the **`BARE_OS_BIN_API`** pragma (coreutils **`runtime.js`** and hand-written stubs such as **`systemctl`** / **`journalctl`**).
 
 Optional **system** image examples: **`etc/bare-os/boot.allow.example`** (copy to **`boot.allow`** when using host **`BARE_OS_BOOT_ALLOWLIST=1`**), **`etc/bare-os/boot.policy.example.json`** (install as **`boot.policy.json`** when using **`BARE_OS_BOOT_POLICY=1`**; v2 fields **`maxExecLineDepth`**, **`denyEnvKeys`**, **`requireProcNodes`**; v3 **`requireKernelCapabilitiesExtendedSeedingPlatform`**, **`requireKernelCapabilitiesRlimitsDelegatesShell`**, **`allowedPearIpcChannels`**, **`denyVfsPrefixes`**, **`maxInitdRestartsPerUnit`**; v4 **`requireKernelCapabilitiesOfflineNetExtensions`**, **`denyExecLineBuiltins`**, **`allowedCtxMethods`**; v9 **`requireKernelCapabilitiesBareModuleCryptoStaging`**, **`requirePearRuntimeRange`**, **`denyBareModuleSpecifierPatterns`**, **`requireBareCryptoMin`**, **`denyKernelSyscalls`**, **`requirePearIpcMin`**, **`extensionSignerPinsV2`**, **`offlineLkgManifestMaxAgeSec`**, **`bootPhasesRequireProcIndexMinSchema`**; v10 **`requireKernelCapabilitiesPearInspectLoggerTls`**, **`requireBareBootMin`**, **`bootPhasesRequireLifecycleMinSchema`**, **`extensionSignerPinsV3`**, …; JSON Schema: [`docs/schemas/boot.policy.schema.json`](../docs/schemas/boot.policy.schema.json)), **`etc/bare-os/kernel.extensions.registry.example.json`** (shape for **`/proc/bare_os/extensions.json`** schema 7), **`etc/bare-os/boot-trace-line.example.json`** and **`etc/bare-os/telemetry-ndjson.example.json`** (shape checks for CI), **`etc/bare-os/rc.profile.full`** (sample full profile referenced from **`profile`**), **`etc/bare-os/crontab.example`** (system-wide cron lines merged ahead of user **`~/.crontab`**), **`etc/bare-os/timers/*.timer.example`** (copy to **`~/.config/bare-os/timers/*.timer`** for **`OnCalendar=`**, **`EveryMs=`**, or **`OnInactiveSec=`** jobs). **`kernel.ext.d`** scripts register into **`/proc/bare_os/extensions.json`** when the booter provides **`ctx.bareOsRegisterKernelExtensionRecord`**.