Add Find Node buzzer admin protobufs

[RCGV1]

What does this PR do?

Adds the protobuf contract for a Find Node buzzer action:

• AdminMessage.find_node_request starts or stops a local audible find-node pattern.
• AdminMessage.find_node_response reports whether the request started, stopped, or could not run because the node has no buzzer or buzzer output is disabled.
• DeviceMetadata.hasBuzzer advertises whether a node has buzzer/audio output usable by this command.

Related PRs:

• Firmware: Add Find Node buzzer admin action firmware#10755
• Apple app: Add Find Node buzzer action Meshtastic-Apple#1973

Checklist before merging

• All top level messages commented
• All enum members have unique descriptions

Verification

• Firmware generated bindings were regenerated from this schema.
• Firmware native admin radio test passed after narrowing the firmware PR scope: platformio test -e native-macos -f test_admin_radio completed 61/61.
• Apple Swift protobufs were regenerated from commit 6566cd61812af44c5a3e77f01db8f72de0a1020a, and the Apple app simulator build passed.
• Local Buf checks were not run because buf is not installed in this environment.

Summary by CodeRabbit

• New Features
  • Added a new “find node” action that can start or stop an audible locator pattern on supported devices.
  • Devices can now report whether they have buzzer support, helping apps show the feature only when available.
• Bug Fixes
  • Improved response handling for the new find-node action, including clear outcomes for supported and unsupported devices.

[Copilot]

Pull request overview

This PR adds new protobuf contract surface for an admin “find node” buzzer action, including a capability flag in device metadata and corresponding admin request/response messages.

Changes:

• Add DeviceMetadata.hasBuzzer to advertise whether a node has usable buzzer/audio output for find-node.
• Add AdminMessage.FindNodeRequest / FindNodeResponse and wire them into AdminMessage.payload_variant.
• Add a nanopb option to size FindNodeResponse.result as an 8-bit integer.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
meshtastic/mesh.proto	Adds DeviceMetadata.hasBuzzer capability flag for clients/firmware to advertise buzzer support.
meshtastic/admin.proto	Introduces find-node request/response message types and new AdminMessage variants to start/stop audible patterns.
meshtastic/admin.options	Adds nanopb sizing option for the new find-node result enum field.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[coderabbitai]

Important

Review skipped

Auto reviews are disabled on base/target branches other than the default branch.

Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: fb9f3441-7251-4e21-8921-7202faee9e56

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

• ✅ Review completed - (🔄 Check again to review again)

---

_{Comment @coderabbitai help to get the list of available commands.}