feat(boards): add Heltec Mesh Node T114

First color-display board on the site (nRF52840 + SX1262 + 1.14" 240x135
ST7789 TFT). Slotted into the Heltec block in boards.ts; Uf2DownloadFlow
maps the T114 id to the bootloader drive name (T114BOOT — verify on
real hardware).

Drive-by: the /flash page subtitle said "download UF2 files for nRF
boards" but the Waveshare RP2040-LoRa is also a UF2 target. Updated to
"nRF52840 and RP2040 boards".

src/components/Uf2DownloadFlow.svelte

@@ -19,9 +19,11 @@
       ? "RAK4631"
       : board.id === "wio_tracker_l1"
         ? "WIO-L1"
-        : board.id === "waveshare_rp2040_lora"
-          ? "RPI-RP2"
-          : "UF2BOOT",
+        : board.id === "heltec_mesh_node_t114"
+          ? "T114BOOT"
+          : board.id === "waveshare_rp2040_lora"
+            ? "RPI-RP2"
+            : "UF2BOOT",
   );
 
   function handleDownload() {

src/lib/boards.ts

@@ -54,6 +54,17 @@ export const boards: BoardDef[] = [
     flashMethod: "web-serial",
     assetPattern: "donglora-heltec_v4-v{version}.bin",
   },
+  {
+    id: "heltec_mesh_node_t114",
+    name: "Heltec Mesh Node T114",
+    mcu: "nRF52840",
+    radio: "SX1262",
+    family: "nrf52840",
+    flashMethod: "uf2",
+    assetPattern: "donglora-heltec_mesh_node_t114-v{version}.uf2",
+    notes:
+      "nRF52840 + SX1262 with a 1.14\" 240×135 ST7789 color TFT — the first donglora board with a color display. Flashes over native USB CDC-ACM via the Adafruit nRF52 UF2 bootloader — double-tap RESET to expose the drive.",
+  },
   {
     id: "lilygo_tbeam_supreme",
     name: "LilyGo T-Beam S3 Supreme",

src/pages/flash.astro

@@ -6,7 +6,7 @@ import Flasher from "../components/Flasher.svelte";
 <Base title="DongLoRa Flasher" description="Flash DongLoRa firmware onto your LoRa board from the browser">
   <h1 class="font-mono text-3xl font-bold mb-2">Firmware Flasher</h1>
   <p class="text-text-muted mb-8">
-    Flash DongLoRa firmware directly from your browser using Web Serial, or download UF2 files for nRF boards.
+    Flash DongLoRa firmware directly from your browser using Web Serial, or download UF2 files for nRF52840 and RP2040 boards.
   </p>
   <Flasher client:load />
 </Base>