Use VQF for GS attitude and improve sensor/demo screens

[stojadin2701]

Summary

• Replace the Ground Station Madgwick estimator with pinned VQF 2.1.2 and remove the now-unused Madgwick vendor library. The shared adapter preserves the board mounting and existing compass/recovery heading convention, converts sensor units, enables VQF gyro-bias and magnetic-disturbance handling, and defines positive pitch as pointing up. Accepting a new calibration resets learned filter state on the navigation task while preserving saved calibration.
• Improve the Sensors and Compass pages with header navigation arrows, a vertical pitch ball, readable degree symbols, and removal of the overlapping footer artifact. The light simulator completes startup before Play/Restart Demo renders, Reboot retains the full startup sequence, and simulator telemetry now uses a realistic default battery voltage.
• Bump Ground Station firmware to 1.3.1.
• Document and surface that Ground Station telemetry updates require Telemetry 1.2.0 or newer. Telemetry 1.1.3 and earlier stop safely before erase/write when bootloader entry is unsupported and require a one-time ST-Link installation; the updater error, confirmation screen, documentation, and ROM updater tests now state this boundary.
• Keep legacy Telemetry 1.1.3 serial control compatible by holding all Ground Station UART transmissions for the receiver's first five seconds. Incoming telemetry remains active, while link settings, version requests, test commands, and updater entry wait until the legacy receiver has enabled DMA reception.
• Update the CATS Flights URL in the repository README.

Validation

ground_station/gs-precommit.ps1 passed at the PR head, including:

• Windows and WSL firmware builds and clang-tidy.
• ROM bootloader tests, including the non-destructive legacy no-entry-ACK path.
• Real VQF integration tests covering 120 poses, vertical pitch limits, gyro axes/units, residual bias, reset, magnetic disturbance/recovery, and invalid inputs.
• Three-phase self-test coverage.
• 21 deterministic simulator scenarios, 12 browser/CLI fixtures, framebuffer checks, and the WebAssembly build.

Browser and visual checks cover navigation, degree symbols, pitch movement/clamping, startup/demo transitions, realistic battery display, and stale-pixel clearing. The display simulator injects angles directly; VQF is exercised separately by the native tests.

Hardware validation

• Built and flashed the current Ground Station 1.3.1 UF2.
• Flashed Telemetry 1.1.3 through ST-Link and started the patched Ground Station before the legacy receiver completed its UART startup. version.json reported 1.1.3 and the live USART2 status was 0x006210D0 with the overrun flag clear.
• Restored the telemetry chip to 1.2.0. STM32CubeProgrammer verified the programmed image and the live firmware tick confirmed that the application was running.

Current Windows firmware binary: 623,232 bytes. Reported static RAM: 67,136 bytes.

Physical VQF heading, tilt response, calibration, magnetic recovery, and navigation task timing/stack headroom remain to be validated on the Ground Station.