Add event_mode options to LocalConfig

[vidplace7]

What does this PR do?

Add event_mode_enabled and event_mode_title to LocalConfig proto.

This should facilitate the firmware conveying "I am in event_mode, burningmesh2025" to clients, which can choose to behave differently (example, load custom Burning Man KML in App when using the event firmware)

Checklist before merging

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

[Copilot]

Pull Request Overview

This PR adds event mode configuration options to the LocalConfig proto message to allow firmware to communicate event-specific information to clients. This enables clients to modify their behavior based on the event context, such as loading custom KML files for specific events like Burning Man.

• Added event_mode_enabled boolean flag to indicate firmware support for event mode
• Added event_mode_title string field to specify the event name/identifier
• Set size constraint for the event title field to 33 characters maximum

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
meshtastic/localonly.proto	Adds two new fields to LocalConfig message for event mode configuration
meshtastic/localonly.options	Defines maximum size constraint for the event_mode_title field

[Copilot]

The comment should clarify the expected format or constraints for the event_mode_title. Consider documenting whether it should be alphanumeric only, lowercase, or follow specific naming conventions since it affects client UI behavior.

Suggested change

	* Title for event mode firmware
	* Ex: "burningmesh2025"
	* Set at compile time, consumed by clients to modify UI behavior
	* Title for event mode firmware.
	* Expected format: alphanumeric, lowercase, no spaces, maximum 32 characters.
	* Example: "burningmesh2025"
	* This value is set at compile time and is consumed by clients to modify UI behavior.

[vidplace7]

Superseded by #739