v2's marker fix proved the install completes, but avdmanager still saw
no system images: it IGNORES ANDROID_SDK_ROOT (and has no --sdk_root),
deriving the SDK root from its own toolsdir — /opt/android in our image,
while packages live on the PVC at /sdk. v3 seeds cmdline-tools into
/sdk/cmdline-tools/latest once and runs avdmanager from there, so it
resolves the PVC as the SDK root.
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