fix(service): update viewport on GL thread per rotation, reuse EGL surface

[kxxoling]

Fix wallpaper covering only a screen corner after rotation

Problem

After rotating the device (landscape ⇄ portrait), the wallpaper only covered a corner region of the screen (bottom-left or bottom-right). The rest of the screen showed the compositor background.

Root cause

Engine.onSurfaceChanged called renderer.onSurfaceChanged on the UI thread. The orthographic matrix update (plain memory) took effect, but glViewport is a GL call and the EGL context is current on the GL thread — a context can only be current on one thread at a time — so the call was silently dropped. The viewport kept the old orientation while the projection used the new one, squeezing the scene into the old viewport rectangle.

Additionally, the EGL window surface was never recreated when the system destroyed and recreated the Surface, leaving swaps silently failing into a dead native window (the swap return value was never checked). This was a latent bug on ROMs that recreate the Surface on rotation.

Fix

Route the surface lifecycle through the GL thread via volatile flags instead of touching GL state from the engine thread:

• Plain resize (typical rotation): the EGL window surface follows the native window size, so only renderer.onSurfaceChanged (viewport + projection) runs on the GL thread — no EGL rebuild, no white flash. The GL surface and textures stay fully reused, matching the pre-fix behavior.
• Surface destroy/recreate: the EGL window surface is released (context kept, so textures/programs survive) and rebuilt from the holder's current Surface, retrying on a later frame if the surface is not valid yet.
• The initial size is seeded from the holder at thread start, since engine notifications may predate thread startup.

On the tested device, rotation resizes the surface in place, so the resize path is the exercised one; the destroy/recreate path is a robustness fix for ROMs that recreate the Surface.

Testing

• Verified on a real device: landscape → portrait → landscape rotations keep the background covering the full screen with no white flash; drag, double-tap reset, and lock/unlock transitions are unaffected.
• compileDebugKotlin, testDebugUnitTest, ktlintCheck pass.