VPAAMP-157: Bring dev_sprint_25_2 to parity with support/2.11.1_8.4_vipa

[pstroffolino]

Reason for Change: Apply the same trickplay-seek rate fix to SeekAfterPrepared() that was already applied to SeekInternal() in PR #1351. When the deferred seek path is taken (eSTATE_INITIALIZED / eSTATE_PREPARING), positional seeks now preserve the trickplay rate and skip the spurious speed=1 notification, consistent with the SeekInternal() behaviour.

• Add three unit tests covering the trickplay seek scenarios:
  • SeekInternal_TrickplayPositionSeek_PreservesRateNoSpeedEvent
  • SeekInternal_TrickplaySeekToLive_ResetsRateAndNotifies
  • SeekInternal_TrickplaySeekToEnd_ResetsRateAndNotifies

[Copilot]

Pull request overview

Aligns dev_sprint_25_2 with support/2.11.1_8.4_vipa for VPAAMP-157 by fixing deferred-seek trickplay behavior so positional seeks preserve the current trickplay rate and avoid emitting a spurious normal-speed event.

Changes:

• Update SeekAfterPrepared() to only reset rate (and trigger a speed-changed notification) for seek-to-live / seek-to-end while in trickplay; preserve rate for positional seeks.
• Add unit tests covering SeekInternal() trickplay seek scenarios (positional seek preserves rate; seek-to-live and seek-to-end reset rate and notify).

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
main_aamp.cpp	Adjusts deferred seek (SeekAfterPrepared) to match SeekInternal trickplay seek rate/notification behavior.
test/utests/tests/PlayerInstanceAAMP/PlayerInstanceAAMPTestsMain.cpp	Adds three unit tests validating SeekInternal trickplay seek rate and notification behavior.