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)

kernel/etc/bare-os/syscalls.example.json

@@ -1,11 +1,11 @@
 {
-  "schemaVersion": 4,
-  "ctxApiVersion": "1.37.0",
+  "schemaVersion": 5,
+  "ctxApiVersion": "1.38.0",
   "posixProfile": {
     "id": "bare-os-posix-like",
-    "version": "1.0.3"
+    "version": "1.0.4"
   },
-  "ops": ["readFile", "writeFile"],
+  "ops": ["readFile", "writeFile", "socket"],
   "opsDetail": [
     { "name": "readFile", "category": "fs", "stability": "stable" },
     { "name": "writeFile", "category": "fs", "stability": "stable" },
@@ -16,16 +16,25 @@
       "posixAlignment": "simulated",
       "mapsTo": ["vfs.readFile", "vfs.writeFile"],
       "errnoHint": "ENOENT"
+    },
+    {
+      "name": "socket",
+      "category": "ipc",
+      "stability": "experimental",
+      "posixAlignment": "ENOTSUP",
+      "mapsTo": ["ctx.bare bare-tcp / bare-dgram"],
+      "errnoHint": "ENOSYS"
     }
   ],
   "posixXsh": {
     "schema": 1,
-    "note": "POSIX.1 XSH names in opsDetail with posixAlignment; not ctx.bareOsSyscall op strings.",
-    "namesCsv": "open,close,read,write,lseek,pipe,dup,dup2,fcntl,poll,select,umask"
+    "note": "POSIX.1 XSH-style names; socket family are ctx.bareOsSyscall ops returning ENOSYS-shaped results.",
+    "namesCsv": "open,close,read,write,lseek,pipe,dup,dup2,fcntl,poll,select,umask,socket,bind,listen,accept,connect,send,recv,shutdown"
   },
   "errnoHints": {
     "ENOENT": 2,
-    "EACCES": 13
+    "EACCES": 13,
+    "ENOSYS": 38
   },
   "fdModel": {
     "schema": 1,
@@ -33,7 +42,7 @@
     "stdio": [0, 1, 2],
     "register": "ctx.bareOsRegisterLogicalFd",
     "processTablePath": "/proc/bare_os/process_table.json",
-    "processTableSchema": 4
+    "processTableSchema": 5
   },
   "signalModel": {
     "schema": 1,