Sprite Atlas content is missing from Player build when "Include in Build" is re-enabled after a previous build had it disabled

Repro steps:

1. Open the attached "IN-145370_6_6_0a7_AtlasTest.zip" project
2. Open the SampleScene
3. In the Project tab, select Assets-> master atlas and make sure “Include in Build” is disabled
4. Go to File->Build Profiles, then “Build and Run” with SampleScene
5. Observe the Player
6. Back in Assets, enable “Include in Build” on the master atlas
7. “Build and Run” again
8. Observe the player

Expected result: In step 5, no Triangle should be visible in the Player. In step 8, a Triangle should be visible in the Player without needing a Clean Build
Actual result: In step 5, no Triangle is visible in the Player (as expected). In step 8, the Triangle is still not visible in the Player until a Clean Build is triggered

Reproducible with: 6000.0.0f1, 6000.0.77f1, 6000.3.18f1, 6000.4.12f1, 6000.5.0f1, 6000.6.0a7

Reproducible on: MacOS 26.5 (M1), Windows 11

Workaround: With “Include in Build” enabled go to “Build Profiles”, use “Clean Build” from the Build dropdown, then launch the player - the Triangle appears

Note: If the first build is made with "Include in Build" already enabled, everything works as intended. To reproduce the bug, the atlas must be built with "Include in Build" disabled first, then re-enabled on a subsequent build.