Fix rotate-to-fullscreen CI checks

[wizdom13]

• Add the missing Javadoc return description for the orientation-eligibility helper
• Refactor the rotate-to-fullscreen eligibility check to avoid the new excessive-parameter warning
• Keep manual fullscreen, PiP, large-screen, and existing eligibility protections unchanged
• Reformat the regression test to satisfy the project line-length rule
• Preserve the merged Auto-switch to fullscreen on device rotation during playback (even with locked orientation) #364 behavior while making the JVM and Android CI lanes reach their real checks