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/nrf9120-pac/src/regulators_ns/dcdcen.rs

@@ -0,0 +1,126 @@
+#[doc = "Register `DCDCEN` reader"]
+pub struct R(crate::R<DCDCEN_SPEC>);
+impl core::ops::Deref for R {
+    type Target = crate::R<DCDCEN_SPEC>;
+    #[inline(always)]
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+impl From<crate::R<DCDCEN_SPEC>> for R {
+    #[inline(always)]
+    fn from(reader: crate::R<DCDCEN_SPEC>) -> Self {
+        R(reader)
+    }
+}
+#[doc = "Register `DCDCEN` writer"]
+pub struct W(crate::W<DCDCEN_SPEC>);
+impl core::ops::Deref for W {
+    type Target = crate::W<DCDCEN_SPEC>;
+    #[inline(always)]
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+impl core::ops::DerefMut for W {
+    #[inline(always)]
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.0
+    }
+}
+impl From<crate::W<DCDCEN_SPEC>> for W {
+    #[inline(always)]
+    fn from(writer: crate::W<DCDCEN_SPEC>) -> Self {
+        W(writer)
+    }
+}
+#[doc = "Field `DCDCEN` reader - Enable DC/DC converter"]
+pub type DCDCEN_R = crate::BitReader<DCDCEN_A>;
+#[doc = "Enable DC/DC converter\n\nValue on reset: 0"]
+#[derive(Clone, Copy, Debug, PartialEq)]
+pub enum DCDCEN_A {
+    #[doc = "0: DC/DC mode is disabled"]
+    DISABLED = 0,
+    #[doc = "1: DC/DC mode is enabled"]
+    ENABLED = 1,
+}
+impl From<DCDCEN_A> for bool {
+    #[inline(always)]
+    fn from(variant: DCDCEN_A) -> Self {
+        variant as u8 != 0
+    }
+}
+impl DCDCEN_R {
+    #[doc = "Get enumerated values variant"]
+    #[inline(always)]
+    pub fn variant(&self) -> DCDCEN_A {
+        match self.bits {
+            false => DCDCEN_A::DISABLED,
+            true => DCDCEN_A::ENABLED,
+        }
+    }
+    #[doc = "Checks if the value of the field is `DISABLED`"]
+    #[inline(always)]
+    pub fn is_disabled(&self) -> bool {
+        *self == DCDCEN_A::DISABLED
+    }
+    #[doc = "Checks if the value of the field is `ENABLED`"]
+    #[inline(always)]
+    pub fn is_enabled(&self) -> bool {
+        *self == DCDCEN_A::ENABLED
+    }
+}
+#[doc = "Field `DCDCEN` writer - Enable DC/DC converter"]
+pub type DCDCEN_W<'a, const O: u8> = crate::BitWriter<'a, u32, DCDCEN_SPEC, DCDCEN_A, O>;
+impl<'a, const O: u8> DCDCEN_W<'a, O> {
+    #[doc = "DC/DC mode is disabled"]
+    #[inline(always)]
+    pub fn disabled(self) -> &'a mut W {
+        self.variant(DCDCEN_A::DISABLED)
+    }
+    #[doc = "DC/DC mode is enabled"]
+    #[inline(always)]
+    pub fn enabled(self) -> &'a mut W {
+        self.variant(DCDCEN_A::ENABLED)
+    }
+}
+impl R {
+    #[doc = "Bit 0 - Enable DC/DC converter"]
+    #[inline(always)]
+    pub fn dcdcen(&self) -> DCDCEN_R {
+        DCDCEN_R::new((self.bits & 1) != 0)
+    }
+}
+impl W {
+    #[doc = "Bit 0 - Enable DC/DC converter"]
+    #[inline(always)]
+    pub fn dcdcen(&mut self) -> DCDCEN_W<0> {
+        DCDCEN_W::new(self)
+    }
+    #[doc = "Writes raw bits to the register."]
+    #[inline(always)]
+    pub unsafe fn bits(&mut self, bits: u32) -> &mut Self {
+        self.0.bits(bits);
+        self
+    }
+}
+#[doc = "Enable DC/DC mode of the main voltage regulator.\n\nThis register you can [`read`](crate::generic::Reg::read), [`write_with_zero`](crate::generic::Reg::write_with_zero), [`reset`](crate::generic::Reg::reset), [`write`](crate::generic::Reg::write), [`modify`](crate::generic::Reg::modify). See [API](https://docs.rs/svd2rust/#read--modify--write-api).\n\nFor information about available fields see [dcdcen](index.html) module"]
+pub struct DCDCEN_SPEC;
+impl crate::RegisterSpec for DCDCEN_SPEC {
+    type Ux = u32;
+}
+#[doc = "`read()` method returns [dcdcen::R](R) reader structure"]
+impl crate::Readable for DCDCEN_SPEC {
+    type Reader = R;
+}
+#[doc = "`write(|w| ..)` method takes [dcdcen::W](W) writer structure"]
+impl crate::Writable for DCDCEN_SPEC {
+    type Writer = W;
+}
+#[doc = "`reset()` method sets DCDCEN to value 0"]
+impl crate::Resettable for DCDCEN_SPEC {
+    #[inline(always)]
+    fn reset_value() -> Self::Ux {
+        0
+    }
+}

vendor/nrf9120-pac/src/regulators_ns/extpofcon.rs

@@ -0,0 +1,126 @@
+#[doc = "Register `EXTPOFCON` reader"]
+pub struct R(crate::R<EXTPOFCON_SPEC>);
+impl core::ops::Deref for R {
+    type Target = crate::R<EXTPOFCON_SPEC>;
+    #[inline(always)]
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+impl From<crate::R<EXTPOFCON_SPEC>> for R {
+    #[inline(always)]
+    fn from(reader: crate::R<EXTPOFCON_SPEC>) -> Self {
+        R(reader)
+    }
+}
+#[doc = "Register `EXTPOFCON` writer"]
+pub struct W(crate::W<EXTPOFCON_SPEC>);
+impl core::ops::Deref for W {
+    type Target = crate::W<EXTPOFCON_SPEC>;
+    #[inline(always)]
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+impl core::ops::DerefMut for W {
+    #[inline(always)]
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.0
+    }
+}
+impl From<crate::W<EXTPOFCON_SPEC>> for W {
+    #[inline(always)]
+    fn from(writer: crate::W<EXTPOFCON_SPEC>) -> Self {
+        W(writer)
+    }
+}
+#[doc = "Field `POF` reader - Enable or disable external power failure warning"]
+pub type POF_R = crate::BitReader<POF_A>;
+#[doc = "Enable or disable external power failure warning\n\nValue on reset: 0"]
+#[derive(Clone, Copy, Debug, PartialEq)]
+pub enum POF_A {
+    #[doc = "0: Disable"]
+    DISABLED = 0,
+    #[doc = "1: Enable"]
+    ENABLED = 1,
+}
+impl From<POF_A> for bool {
+    #[inline(always)]
+    fn from(variant: POF_A) -> Self {
+        variant as u8 != 0
+    }
+}
+impl POF_R {
+    #[doc = "Get enumerated values variant"]
+    #[inline(always)]
+    pub fn variant(&self) -> POF_A {
+        match self.bits {
+            false => POF_A::DISABLED,
+            true => POF_A::ENABLED,
+        }
+    }
+    #[doc = "Checks if the value of the field is `DISABLED`"]
+    #[inline(always)]
+    pub fn is_disabled(&self) -> bool {
+        *self == POF_A::DISABLED
+    }
+    #[doc = "Checks if the value of the field is `ENABLED`"]
+    #[inline(always)]
+    pub fn is_enabled(&self) -> bool {
+        *self == POF_A::ENABLED
+    }
+}
+#[doc = "Field `POF` writer - Enable or disable external power failure warning"]
+pub type POF_W<'a, const O: u8> = crate::BitWriter<'a, u32, EXTPOFCON_SPEC, POF_A, O>;
+impl<'a, const O: u8> POF_W<'a, O> {
+    #[doc = "Disable"]
+    #[inline(always)]
+    pub fn disabled(self) -> &'a mut W {
+        self.variant(POF_A::DISABLED)
+    }
+    #[doc = "Enable"]
+    #[inline(always)]
+    pub fn enabled(self) -> &'a mut W {
+        self.variant(POF_A::ENABLED)
+    }
+}
+impl R {
+    #[doc = "Bit 0 - Enable or disable external power failure warning"]
+    #[inline(always)]
+    pub fn pof(&self) -> POF_R {
+        POF_R::new((self.bits & 1) != 0)
+    }
+}
+impl W {
+    #[doc = "Bit 0 - Enable or disable external power failure warning"]
+    #[inline(always)]
+    pub fn pof(&mut self) -> POF_W<0> {
+        POF_W::new(self)
+    }
+    #[doc = "Writes raw bits to the register."]
+    #[inline(always)]
+    pub unsafe fn bits(&mut self, bits: u32) -> &mut Self {
+        self.0.bits(bits);
+        self
+    }
+}
+#[doc = "External power failure warning configuration\n\nThis register you can [`read`](crate::generic::Reg::read), [`write_with_zero`](crate::generic::Reg::write_with_zero), [`reset`](crate::generic::Reg::reset), [`write`](crate::generic::Reg::write), [`modify`](crate::generic::Reg::modify). See [API](https://docs.rs/svd2rust/#read--modify--write-api).\n\nFor information about available fields see [extpofcon](index.html) module"]
+pub struct EXTPOFCON_SPEC;
+impl crate::RegisterSpec for EXTPOFCON_SPEC {
+    type Ux = u32;
+}
+#[doc = "`read()` method returns [extpofcon::R](R) reader structure"]
+impl crate::Readable for EXTPOFCON_SPEC {
+    type Reader = R;
+}
+#[doc = "`write(|w| ..)` method takes [extpofcon::W](W) writer structure"]
+impl crate::Writable for EXTPOFCON_SPEC {
+    type Writer = W;
+}
+#[doc = "`reset()` method sets EXTPOFCON to value 0"]
+impl crate::Resettable for EXTPOFCON_SPEC {
+    #[inline(always)]
+    fn reset_value() -> Self::Ux {
+        0
+    }
+}

vendor/nrf9120-pac/src/regulators_ns/systemoff.rs

@@ -0,0 +1,71 @@
+#[doc = "Register `SYSTEMOFF` writer"]
+pub struct W(crate::W<SYSTEMOFF_SPEC>);
+impl core::ops::Deref for W {
+    type Target = crate::W<SYSTEMOFF_SPEC>;
+    #[inline(always)]
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+impl core::ops::DerefMut for W {
+    #[inline(always)]
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.0
+    }
+}
+impl From<crate::W<SYSTEMOFF_SPEC>> for W {
+    #[inline(always)]
+    fn from(writer: crate::W<SYSTEMOFF_SPEC>) -> Self {
+        W(writer)
+    }
+}
+#[doc = "Enable System OFF mode\n\nValue on reset: 0"]
+#[derive(Clone, Copy, Debug, PartialEq)]
+pub enum SYSTEMOFF_AW {
+    #[doc = "1: Enable System OFF mode"]
+    ENABLE = 1,
+}
+impl From<SYSTEMOFF_AW> for bool {
+    #[inline(always)]
+    fn from(variant: SYSTEMOFF_AW) -> Self {
+        variant as u8 != 0
+    }
+}
+#[doc = "Field `SYSTEMOFF` writer - Enable System OFF mode"]
+pub type SYSTEMOFF_W<'a, const O: u8> = crate::BitWriter<'a, u32, SYSTEMOFF_SPEC, SYSTEMOFF_AW, O>;
+impl<'a, const O: u8> SYSTEMOFF_W<'a, O> {
+    #[doc = "Enable System OFF mode"]
+    #[inline(always)]
+    pub fn enable(self) -> &'a mut W {
+        self.variant(SYSTEMOFF_AW::ENABLE)
+    }
+}
+impl W {
+    #[doc = "Bit 0 - Enable System OFF mode"]
+    #[inline(always)]
+    pub fn systemoff(&mut self) -> SYSTEMOFF_W<0> {
+        SYSTEMOFF_W::new(self)
+    }
+    #[doc = "Writes raw bits to the register."]
+    #[inline(always)]
+    pub unsafe fn bits(&mut self, bits: u32) -> &mut Self {
+        self.0.bits(bits);
+        self
+    }
+}
+#[doc = "System OFF register\n\nThis register you can [`write_with_zero`](crate::generic::Reg::write_with_zero), [`reset`](crate::generic::Reg::reset), [`write`](crate::generic::Reg::write). See [API](https://docs.rs/svd2rust/#read--modify--write-api).\n\nFor information about available fields see [systemoff](index.html) module"]
+pub struct SYSTEMOFF_SPEC;
+impl crate::RegisterSpec for SYSTEMOFF_SPEC {
+    type Ux = u32;
+}
+#[doc = "`write(|w| ..)` method takes [systemoff::W](W) writer structure"]
+impl crate::Writable for SYSTEMOFF_SPEC {
+    type Writer = W;
+}
+#[doc = "`reset()` method sets SYSTEMOFF to value 0"]
+impl crate::Resettable for SYSTEMOFF_SPEC {
+    #[inline(always)]
+    fn reset_value() -> Self::Ux {
+        0
+    }
+}