feat(ui-lvgl): offline raster map from the microSD

Map screen (Home > Map): Web-Mercator tiles from /maps/{z}/{x}/{y}.png on
the card (Meshtastic MUI layout; per-column TPK1 .pak also read), drag to
pan, +/- zoom, re-centre/follow GPS, Nearby nodes with a position as
markers opening node detail. Tiles decode one per loop pass into a
12-slot RGB565 cache in PSRAM. map/TileProvider.h is the swap point for a
later vector renderer: the screen only calls renderTile(). The tile set's
credit line comes from maps/attribution.txt.

L2 mounts the card over SDMMC 1-bit (CLK 2, CMD 3, D0 1). LVGL's lodepng
is enabled; note its LVGL patch returns an lv_draw_buf_t*, not pixels.
LVGL pool 2 MB for PNG decoding. Fonts gain map / users icons.

tools/maps/fetch_tiles.py prepares a card for an area (presets for
Poland), requires an explicit tile URL (tile.openstreetmap.org blocks
offline use) and stops on placeholder images. The LVGL sim preloads
web/maps into the L2's /sdcard and puts its GPS on Kraków.

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

solo/wio-tracker-l2/platformio.ini

@@ -65,3 +65,5 @@ lib_deps =
   ${Wio_Tracker_L2.lib_deps}
   densaugeo/base64 @ ~1.4.0
   lvgl/lvgl @ 9.2.2   ; pinned: bump deliberately, re-test on hardware
+  SD_MMC              ; map tiles on the microSD (framework library)
+  FS