[tintinhamans]

Combines the device reset fixes from #632, #634 and the previous version of this PR. A device reset happens on alt-tab in fullscreen, a lock screen, a UAC prompt or a resolution change, and each of these fixes covers a different way it went wrong. All commits except the last are cherry-pick -x of merged upstream commits.

• bugfix(w3dtreebuffer): Refill the tree buffers after a device reset TheSuperHackers/GeneralsGameCode#3449 bugfix(w3dtreebuffer): Refill the tree buffers after a device reset
• fix(flatheightmap): Fix flat terrain tiles leaking on device reset TheSuperHackers/GeneralsGameCode#3479 fix(flatheightmap): Fix flat terrain tiles leaking on device reset
• bugfix(shroud): Copy the shroud to its texture manually instead of with CopyRects TheSuperHackers/GeneralsGameCode#3440 bugfix(shroud): Copy the shroud to its texture manually instead of with CopyRects, plus its follow-up that fills every row of the final fog data
• fix(dx8wrapper): Release the cached textures at shutdown TheSuperHackers/GeneralsGameCode#3543 fix(dx8wrapper): Release the cached textures at shutdown
• fix(dx8): Unbind device resources before Reset, the same change as bugfix(dx8): Unbind device resources before Reset TheSuperHackers/GeneralsGameCode#3450, which is approved but not merged yet

Shroud: the shroud was uploaded with CopyRects every frame. On NVIDIA the driver reserves memory for each call and allocates it all at the next reset, so after a long match one reset could take hundreds of MB and the 32-bit process ran out of address space (CLIENT-55X). On the upstream build a 10 minute skirmish followed by a forced reset lost 316 MB on main and nothing with this change, and W3DShroud::render went from 0.032 ms to 0.006 ms per frame.

Reset: Reset_Device could crash in the driver (DestroyResource during Reset) while the device still had a vertex buffer, index buffer, texture or render target bound. Buffers are now unbound once the device can be reset, render states are invalidated and the render target is reset before Reset(), and the device is left alone until a Reset() succeeds. Reproduced on the upstream retail build on an Intel UHD 770 and an RTX 4070 Ti: a bound render target plus a forced device loss failed Reset on every frame forever, with this change both reset cleanly.

Both GeneralsMD and Generals are changed where the code exists twice. The code of every commit is identical to the separate PRs it replaces.

Tested: Zero Hour (z_generals) builds here. The shroud and reset measurements above were made on the upstream build.