chore: massive repo reorganization

firmware/src/board/traits.rs

@@ -0,0 +1,31 @@
+//! Board abstraction trait.
+//!
+//! Every board must implement [`LoRaBoard`]. The compiler enforces completeness —
+//! missing constants or methods are compile errors, not runtime surprises.
+//!
+//! Board modules also export concrete types (`RadioParts`, `UsbParts`,
+//! `DisplayParts`, `RadioDriver`, `UsbDriver`, `DisplayI2c`) that the tasks
+//! use directly. The trait verifies metadata and initialization; the types
+//! verify hardware compatibility.
+//!
+//! See `src/board/PORTING.md` for a step-by-step guide to adding a new board.
+
+/// Compile-time contract for a DongLoRa board.
+///
+/// Every board's `Board` struct must implement this trait. It verifies that
+/// the board provides all required metadata and initialization methods.
+/// The tasks use the board's concrete types directly (not the trait's
+/// associated types) because Embassy tasks must be concrete.
+pub trait LoRaBoard {
+    /// Human-readable board name (shown on display splash screen).
+    const NAME: &'static str;
+
+    /// TX power range in dBm (min, max) for this board's radio + PA.
+    const TX_POWER_RANGE: (i8, i8);
+
+    /// Initialize the board hardware.
+    fn init() -> Self;
+
+    /// Read the board's unique hardware address (MAC, device ID, etc.).
+    fn mac_address() -> [u8; 6];
+}