feat(booter): cache syscalls proc JSON, net tuning hints, /dev/shm unlink, POSIX/docs sync

- Cache /proc/bare_os/syscalls.json until warm read cache clear; invalidate with vfs.bareOsClearWarmReadCaches
- net_summary: optional udxTuning / hyperswarmTuning from BARE_OS_UDX_* / BARE_OS_HYPERSWARM_* JSON
- Metric: operator.corestore_snapshot_hint on bareOsCorestoreSnapshotHint
- pathconf: _PC_NAME_MAX 128 under /dev/shm
- vfs: fix unlink for /dev/shm segments; add roundtrip test
- protocol: bareOsIsAllowedSeedRpcMethodShort + tests
- getconf: _POSIX_SHARED_MEMORY_OBJECTS, _POSIX_MESSAGE_PASSING, _POSIX_ASYNCHRONOUS_IO + test
- microbench: syscall suite (syscalls proc JSON stringify)
- JSON Schema bare-os-syscalls.schema.json schemaVersion 5; posix-conformance-matrix ops = getconf
- Docs: blind-relay security note, compat matrix (1.38.0 / 1.0.4), handbook 04/09, appendix, OTA note
- Pear: document host coupling in compatibility-matrix (no pear-runtime manifest entry)

docs/deployment/OTA_AND_BUNDLES.md

@@ -19,6 +19,7 @@ Bare OS aligns with the **Holepunch** toolchain for shipping JavaScript as **Bar
 - **System image**: `kernel/` is staged to the **system Hyperdrive** by **`bare-os-seeder`**; the booter never falls back to a git checkout for production boot.
 - **Ctx / API semver**: bump **`BARE_OS_CTX_API_VERSION`** when guest-visible `ctx` behavior changes; record it in [compatibility-matrix.md](../reference/compatibility-matrix.md).
 - **Offline / LKG**: document **`BARE_OS_OFFLINE_LKG_BOOT`** and related env in [environment appendix](../reference/environment-and-posix-appendix.md).
+- **Warm cache + proc**: **`bareOsVfsBatchWrite`** clears **`/bin`** / **`/lib/bare`** warm read caches and increments **`vfs.warm_read_cache_invalidate_batch`**; the same path clears the **cached** **`/proc/bare_os/syscalls.json`** text so replication swaps cannot serve stale syscall metadata. **`ctx.bareOsCorestoreSnapshotHint()`** increments **`operator.corestore_snapshot_hint`** for operator dashboards.
 
 ## Reproducibility checklist