SF: Remove *DisplayId::tryCast usage from ScreenCaptureOutput

Work towards DisplayId opaqueness by eliminating call-sites to APIs that
parse the display ID values directly. One such site is
ScreenCaptureOutput.

Replace all calls to *DisplayId::tryCast with local calls to cached
display variant.

Flag: com.android.graphics.surfaceflinger.flags.stable_edid_ids
Bug: 390690584
Test: libcompositionengine_test && libsurfaceflinger_unittest
Change-Id: Ic83a2b2bfa6fc98b1d0fccc60f450d1587c2cc34