Block coordinate traffic on configured event channels (#11045)

* Block coordinate traffic on configured event channels

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

* Suppress event coordinates in reliable relay paths

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

* Reject blocked phone coordinates before rate limiting

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

* Prevent event coordinates from reaching MQTT

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

* Add event coordinate policy preference

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

* Test event coordinate policy in native CI

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

* Make event policy test tolerate a full NodeDB

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

* Test Router event coordinate enforcement

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

* Test PhoneAPI event coordinate retry handling

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

* Test reliable event coordinate suppression

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

* Test MQTT event coordinate suppression

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

* Run event policy behavioral suites in native CI

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

* tests: address CodeRabbit review feedback

- test_event_channel_phone_api: complete the setUp/tearDown save-restore
  pair. GlobalState now carries cryptLock and myNodeInfo; setUp() nulls
  cryptLock before constructing MockRouter (Router's ctor asserts it is
  unset), and tearDown() restores both so the suite leaves no global
  mutated. Not reachable today - the globals start null in this binary -
  but the pair was asymmetric.

- Replace the strcpy calls this branch added on Channel.settings.name
  (char[12]) with the bounded form the rest of the test tree already uses,
  strncpy(dst, src, sizeof(dst) - 1). Covers the flagged site in
  test_nexthop_routing plus the six equivalents in
  test_event_channel_phone_api, test_mqtt and test_position_precision,
  which trip the same ast-grep dangerous-buffer-functions-cpp rule.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

---------

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Co-authored-by: Ben Meadors <benmmeadors@gmail.com>
Co-authored-by: Claude Opus 5 <noreply@anthropic.com>

userPrefs.jsonc

@@ -25,6 +25,7 @@
   // "USERPREFS_CONFIG_DEVICE_ROLE": "meshtastic_Config_DeviceConfig_Role_CLIENT", // Defaults to CLIENT. ROUTER*, and LOST AND FOUND roles are restricted.
   // "USERPREFS_EVENT_MODE": "1",
   // "USERPREFS_EVENT_MODE_HOP_LIMIT": "3", // Event-mode default and firmware-generated/relay hop cap (0-7; default 3)
+  // "USERPREFS_BLOCK_POSITION_ON_EVENT_CHANNEL": "1", // Block location TX + discard inbound location on channels keyed with USERPREFS_CHANNEL_0_PSK. Defaults on under EVENT_MODE.
   // "USERPREFS_TMM_APPLY_TO_PRIVATE_CHANNELS": "1", // Extend TMM position dedup and precision clamping to private/custom-key channels (default: well-known channels only)
   // "USERPREFS_FIRMWARE_EDITION": "meshtastic_FirmwareEdition_BURNING_MAN",
   // "USERPREFS_FIXED_BLUETOOTH": "121212",