fix(l2): WiFi fails to start or join - big statics and task stacks to PSRAM

WiFi starts and joins on internal RAM: ~42 KB the first time, ~25 KB after,
more for WPA. Free internal RAM had shrunk to ~20 KB after opening the map
(the tile decoder's 12 KB stack, the 32 KB I-cache, the DMA draw buffers,
UI statics), so a scan failed at once (esp_wifi_init: no memory) and a join
during a tile download timed out (AUTH_EXPIRE).

- ESP-IDF: CONFIG_SPIRAM_ALLOW_BSS_SEG_EXTERNAL_MEMORY, and the esp_timer
  task stack 8 -> 4 KB (it uses ~0.4 KB). Rebuild the framework libs:
  pio run -e Wio_Tracker_L2_idf_libs.
- PSRAM_BSS (EXT_RAM_BSS_ATTR) on the UI's big statics: QR codes, map
  state, charts, lists. .dram0.bss 115 -> 66 KB.
- The tile decoder's and fetcher's task stacks in PSRAM.

Free internal RAM, idle: 48 -> 105 KB; WiFi up: 57 KB, 29 KB at the
lowest while downloading tiles.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

examples/companion_radio/ui-lvgl/map/TileCache.h

@@ -55,7 +55,10 @@ public:
     _job_stale = false;
     _job_state = JOB_RUNNING;
 #if defined(ESP32)
-    if (!_task && xTaskCreatePinnedToCore(jobTask, "tiles", 12288, this, tskIDLE_PRIORITY + 1, &_task, 0) != pdPASS) {
+    // The stack in PSRAM: internal RAM is what WiFi starts on (it fails to
+    // with ~25 KB left), and the task only reads the SD card, never the flash.
+    if (!_task && xTaskCreatePinnedToCoreWithCaps(jobTask, "tiles", 12288, this, tskIDLE_PRIORITY + 1, &_task, 0,
+                                                  MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT) != pdPASS) {
       _task = nullptr;
       runJob();   // no task: here, as before
       return true;

examples/companion_radio/ui-lvgl/map/VectorLabels.h

@@ -147,7 +147,7 @@ static void layout(double left, double top, int w, int h, int z, bool on, int bo
 
   // Greedy placement: the icon, then the text right / left / above / below it.
   struct Box { int16_t x1, y1, x2, y2; };
-  static Box used[MAX_PLACED * 2 + 8];
+  static PSRAM_BSS Box used[MAX_PLACED * 2 + 8];
   int nu = 0;
   // The map's controls: button columns, the zoom pill between them, scale /
   // credit and the centre button above the bottom bar, the bar.

examples/companion_radio/ui-lvgl/map/VectorPacks.h

@@ -206,6 +206,6 @@ private:
   }
 };
 
-static VectorPacks s_vpacks;
+static PSRAM_BSS VectorPacks s_vpacks;
 
 }  // namespace mapview