feat(lvgl-module): complete canvas API export for GameBoy emulator
- canvas: add missing getters/setters (get_buf, get_image, get_px, get_draw_buf,
set_palette, copy_buf, init_layer, finish_layer, buf_size)
- draw_buf: export create/destroy/init/dup/copy/goto/width_to_stride/align/palette/from_image/to_image
- draw layer: create + alloc_buf
- image: scale/rotation/pivot/offset for GB integer upscaling
- style: transform_scale/pivot for fallback path
Enables ELF apps to use full LVGL9 canvas docs API:
- 160x144 raw buffer + lv_image_set_scale 2x/3x
- layer init/finish for direct draw calls
- palette for indexed GB modes
Test: GameBoy app builds clean (0 missing symbols) vs 5.5.2 SDK
Fixes missing symbol errors that previously required commented-out scaling workaround
Adolfo Reyna
ff3eeacaf7