v0.2.0 — configurable hop limit (default 0)

MeshCore mtbeacon v0.2.0

New: configurable Meshtastic hop limit — default 0.

• The beacon's Meshtastic packets (presence NodeInfo/Position and text) now go out at
  0 hops by default, so they're heard only by direct neighbors and are never
  rebroadcast across the Meshtastic network — a light-footprint default for a foreign beacon.
• New CLI verb: mtbeacon hops <0-3> (capped at 3). Shown as h<N> in mtbeacon status.

Upgrade note: the persisted beacon config layout changed (MAGIC bump), so on first boot
after flashing v0.2.0 the beacon config resets to defaults (beacon starts disabled —
run mtbeacon on and re-apply any custom region/preset/text).

63 boards (nRF52 / ESP32-S3/C3/C6 / RP2040 / STM32WL). ESP32 boards include a -merged.bin
full-install image (bootloader + app) plus the app-only update .bin.