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-synopsys-usb-otg/src/ral/mod.rs

@@ -0,0 +1,118 @@
+#![allow(non_snake_case)]
+
+pub mod instances;
+pub mod peripherals;
+pub mod stm32f429;
+
+pub use ral_registers as register;
+pub use ral_registers::{modify_reg, read_reg, write_reg};
+
+pub mod otg_global {
+    #[cfg(feature = "fs")]
+    pub use super::stm32f429::otg_fs_global::OTG_FS_GLOBAL as OTG_GLOBAL;
+    #[cfg(feature = "fs")]
+    pub use super::stm32f429::otg_fs_global::*;
+    #[cfg(feature = "hs")]
+    pub use super::stm32f429::otg_hs_global::OTG_HS_GLOBAL as OTG_GLOBAL;
+    #[cfg(feature = "hs")]
+    pub use super::stm32f429::otg_hs_global::*;
+}
+
+pub mod otg_device {
+    #[cfg(feature = "fs")]
+    pub use super::stm32f429::otg_fs_device::OTG_FS_DEVICE as OTG_DEVICE;
+    #[cfg(feature = "fs")]
+    pub use super::stm32f429::otg_fs_device::*;
+    #[cfg(feature = "hs")]
+    pub use super::stm32f429::otg_hs_device::OTG_HS_DEVICE as OTG_DEVICE;
+    #[cfg(feature = "hs")]
+    pub use super::stm32f429::otg_hs_device::*;
+}
+
+pub mod otg_pwrclk {
+    #[cfg(feature = "fs")]
+    pub use super::stm32f429::otg_s_pwrclk::OTG_FS_PWRCLK as OTG_PWRCLK;
+    #[cfg(feature = "hs")]
+    pub use super::stm32f429::otg_s_pwrclk::OTG_HS_PWRCLK as OTG_PWRCLK;
+    pub use super::stm32f429::otg_s_pwrclk::*;
+}
+
+pub mod otg_global_dieptxfx {
+    use super::register::RWRegister;
+
+    #[cfg(feature = "fs")]
+    pub use super::stm32f429::otg_fs_global::DIEPTXF1 as DIEPTXFx;
+    #[cfg(feature = "hs")]
+    pub use super::stm32f429::otg_fs_global::DIEPTXF1 as DIEPTXFx;
+
+    pub struct RegisterBlock {
+        pub DIEPTXFx: RWRegister<u32>,
+    }
+}
+
+pub mod endpoint_in {
+    use super::register::RWRegister;
+
+    #[cfg(feature = "fs")]
+    pub use super::stm32f429::otg_fs_device::{
+        DIEPCTL1 as DIEPCTL, DIEPINT1 as DIEPINT, DIEPTSIZ1 as DIEPTSIZ, DTXFSTS1 as DTXFSTS,
+    };
+
+    #[cfg(feature = "hs")]
+    pub use super::stm32f429::otg_hs_device::{
+        DIEPCTL1 as DIEPCTL, DIEPINT1 as DIEPINT, DIEPTSIZ1 as DIEPTSIZ, DTXFSTS1 as DTXFSTS,
+    };
+
+    pub struct RegisterBlock {
+        pub DIEPCTL: RWRegister<u32>,
+        _reserved0: u32,
+        pub DIEPINT: RWRegister<u32>,
+        _reserved1: u32,
+        pub DIEPTSIZ: RWRegister<u32>,
+        _reserved2: u32,
+        pub DTXFSTS: RWRegister<u32>,
+        _reserved3: u32,
+    }
+}
+
+pub mod endpoint0_out {
+    use super::register::RWRegister;
+
+    #[cfg(feature = "fs")]
+    pub use super::stm32f429::otg_fs_device::{DOEPCTL0, DOEPINT0, DOEPTSIZ0};
+
+    #[cfg(feature = "hs")]
+    pub use super::stm32f429::otg_hs_device::{DOEPCTL0, DOEPINT0, DOEPTSIZ0};
+
+    pub struct RegisterBlock {
+        pub DOEPCTL0: RWRegister<u32>,
+        _reserved0: u32,
+        pub DOEPINT0: RWRegister<u32>,
+        _reserved1: u32,
+        pub DOEPTSIZ0: RWRegister<u32>,
+        _reserved2: [u32; 3],
+    }
+}
+
+pub mod endpoint_out {
+    use super::register::RWRegister;
+
+    #[cfg(feature = "fs")]
+    pub use super::stm32f429::otg_fs_device::{
+        DOEPCTL1 as DOEPCTL, DOEPINT1 as DOEPINT, DOEPTSIZ1 as DOEPTSIZ,
+    };
+
+    #[cfg(feature = "hs")]
+    pub use super::stm32f429::otg_hs_device::{
+        DOEPCTL1 as DOEPCTL, DOEPINT1 as DOEPINT, DOEPTSIZ1 as DOEPTSIZ,
+    };
+
+    pub struct RegisterBlock {
+        pub DOEPCTL: RWRegister<u32>,
+        _reserved0: u32,
+        pub DOEPINT: RWRegister<u32>,
+        _reserved1: u32,
+        pub DOEPTSIZ: RWRegister<u32>,
+        _reserved2: [u32; 3],
+    }
+}