Add two-profile LoRa operation and radio CLI regression coverage

Implement radio2, tempradio2, radioat2 and tempradioat2 across Mesh roles,
with RX-only/RX+TX operation, optional preambles and persistent cross-TX
policy. Keep temporary OTA traffic on its profile by default and maintain
independent retry ownership and backoff for each profile.

Use slow-first receive scanning with 4.8-symbol visits and automatic
preambles rounded up in steps of eight. Preserve pending RX, restore power
saving on exit, and discard work bound to changed or expired profiles.

Restore the infrastructure path.hash.mode setter and report unsupported
extra.sf settings consistently. Add CLI, scheduling, scan and retry tests,
setup documentation, and the V4/XIAO hardware validation results.

Validation: 1,422 native tests, eight KISS tests, 63 final focused profile
tests, 18 checks from the staged source, sanitizer-enabled OTA transfers,
and builds for V4 Mesh roles, Full XIAO Companion and nRF52 T1000-E.
Hardware checks cover reception, cross-TX policy, expiry, reboot and OTA
discovery while receiving main-channel adverts.

test/test_path_hash_cli.py

@@ -0,0 +1,65 @@
+"""Exercise the production infrastructure setter and its persistence boundary."""
+from pathlib import Path
+import shutil
+import subprocess
+import tempfile
+import unittest
+from test_replay_reset_integration import extract_braced
+
+ROOT = Path(__file__).resolve().parents[1]
+
+
+class PathHashCLITest(unittest.TestCase):
+    def test_production_setter(self):
+        compiler = shutil.which('g++') or shutil.which('clang++')
+        self.assertIsNotNone(compiler, 'Host C++ compiler required')
+        source = (ROOT/'src/helpers/CommonCLI.cpp').read_text(encoding='utf-8')
+        setter = extract_braced(source, 'void CommonCLI::handleSetCmd(')
+        branch = extract_braced(setter, 'if (strncmp(config, "path.hash.mode", 14)')
+        fixture = r'''
+#include <cassert>
+#include <initializer_list>
+#include <helpers/CLICommandUtils.h>
+struct CLI {
+  struct Prefs { uint8_t path_hash_mode = 0; } prefs;
+  Prefs* _prefs = &prefs;
+  unsigned saves = 0;
+  void savePrefs() { ++saves; }
+  void set(const char* config, char* reply) {
+''' + branch + r'''
+    strcpy(reply, "unknown config");
+  }
+};
+int main() {
+  CLI cli; char reply[160];
+  for (unsigned mode : {0u, 1u, 2u}) {
+    char command[64]; sprintf(command,"path.hash.mode %u",mode);
+    unsigned saves=cli.saves;
+    cli.set(command,reply);
+    assert(strcmp(reply,"OK")==0);
+    assert(cli.prefs.path_hash_mode==mode && cli.saves==saves+1);
+  }
+  cli.set("path.hash.mode\t1 ",reply);
+  assert(strcmp(reply,"OK")==0 && cli.prefs.path_hash_mode==1);
+  for (const char* value : {"", " ", " -1", " 3", " 256", " 4294967296", " nope", " 1x", " 1 2"}) {
+    char command[80]; sprintf(command,"path.hash.mode%s",value);
+    unsigned saves=cli.saves;
+    cli.set(command,reply);
+    assert(strcmp(reply,"Error, must be 0,1, or 2")==0);
+    assert(cli.prefs.path_hash_mode==1 && cli.saves==saves);
+  }
+  cli.set("path.hash.mode.extra 2",reply);
+  assert(strcmp(reply,"unknown config")==0 && cli.prefs.path_hash_mode==1);
+}
+'''
+        with tempfile.TemporaryDirectory() as directory:
+            cpp = Path(directory)/'test.cpp'
+            exe = Path(directory)/'test.exe'
+            cpp.write_text(fixture, encoding='utf-8')
+            subprocess.run([compiler, '-std=c++11', '-Wall', '-Wextra', '-Werror',
+                            '-I', str(ROOT/'src'), str(cpp), '-o', str(exe)], check=True)
+            subprocess.run([str(exe)], check=True)
+
+
+if __name__ == '__main__':
+    unittest.main()