Fix DV7 black screen issue on Exynos chips by safely stripping MediaFormat profile keys during fallback

[KennyPhan123]

Describe the bug
When the dv7Fallback preference is enabled, Exynos devices (e.g., Samsung A54/A55/A56) play audio but show a completely black screen for Dolby Vision Profile 7 videos. The Exynos hardware HEVC decoder silently drops frames instead of throwing a decoding exception when the MediaFormat contains KEY_PROFILE = 128 (HEVCProfileMain10HDR10Plus/DV) and KEY_COLOR_TRANSFER_REQUEST.

This issue does not exist in older ExoPlayer versions (e.g., JustPlayer) because they do not send KEY_COLOR_TRANSFER_REQUEST.

Solution
This PR fixes the issue by wrapping the MediaCodecAdapter.Factory inside NextRenderersFactory.
When dv7Fallback is true and the stream is VIDEO_DOLBY_VISION, it aggressively strips KEY_PROFILE and KEY_COLOR_TRANSFER_REQUEST from the MediaFormat before creating the decoder. This forces the Exynos hardware decoder to treat it as a generic HEVC stream and successfully output HDR frames without silently dropping them.

Testing
Tested and confirmed working perfectly on Samsung A56 5G (Exynos chip).