Remove unused Brookesia integration and retain native brightness control

[Y1hsiaochunnn]

The board pack contains no Brookesia application, so its optional HAL adapter and application profiles are unused scope. Remove that directory and its dedicated CI while retaining the framework-independent AMOLED brightness helper and every board definition.

• Remove integrations/brookesia_hal_custom/, its application defaults, and the adapter-selection CLI and build-matrix dimension.
• Keep boards/, include/waveshare_amoled.h, component registration, and the Board Manager test application byte-identical to the base. Runtime QSPI brightness control remains available through waveshare_amoled_set_brightness().
• Keep all four board profiles on ESP-IDF v5.5.5 and v6.1, for eight builds. Preserve source attribution and licenses; simplify the brightness and CI documentation.
• Bump the component to 0.1.1 for automatic publication after merging. Applications that explicitly selected the removed optional adapter must remove that dependency; ordinary Board Manager applications keep the same API.

Validation for 8f7fc09: 22 Python tests, seven release-operation tests, actionlint, metadata/catalog/navigation checks, and Markdown audit passed. The packaged archive contains four board definitions, the unchanged brightness helper, and no framework-adapter directory. All eight local builds passed on this commit, with no Brookesia dependency resolved. All eight PR Actions builds, metadata checks, and the aggregate check also passed on this commit. No hardware-facing source or configuration is changed; physical board testing remains separate.