feat: add display UI with splash screen, dashboard, and RSSI sparkline

Implement full SSD1306 OLED display support:
- Splash screen on boot (1.5s) with project name, version, board
- Dashboard showing radio state, config, counters, RSSI/SNR
- RSSI history sparkline (64-sample ring buffer, 2px-wide bars)
- DisplayOn/DisplayOff host commands routed via dedicated channel
- Pure render functions against generic DrawTarget (no hardware coupling)
- Display on/off control bypasses radio task entirely

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

vendor/esp-backtrace/CHANGELOG.md

@@ -0,0 +1,63 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+### Added
+
+### Changed
+
+### Fixed
+
+### Removed
+
+## 0.14.2 - 2024-10-10
+
+### Fixed
+
+- Fix build when not using `panic-handler` (#2257)
+
+## 0.14.1 - 2024-09-06
+
+### Added
+
+### Changed
+
+- Print a more helpful message in case of a `Cp0Disabled` exception (#2061)
+
+### Fixed
+
+### Removed
+
+## 0.14.0 - 2024-08-29
+
+### Added
+
+- Add custom-pre-backtrace feature (#1822)
+
+### Changed
+
+- Improve panic message printing (#1823)
+
+## 0.13.0 - 2024-07-16
+
+No changes - published to avoid conflicts with `esp-println`
+
+## 0.12.2 - 2024-07-15
+
+### Changed
+
+- Remove build script check for `nightly-2024-06-12` (#1788)
+
+## 0.12.1 - 2024-06-19
+
+### Fixed
+
+- Fix compilation for nightly after 2024-06-12. (#1681)
+- Only prints float registers on targets which have them. (#1690)
+
+[Unreleased]: https://github.com/esp-rs/esp-hal/commits/main/esp-backtrace?since=2024-10-10