find_all returns before waiting for a later screenshot match #71

Describe the bug

DesktopBot.find_all returns immediately when its first screenshot contains no match, even if waiting_time has not expired. The loop checks if not eles, but locate_all_opencv returns a generator, and an empty generator object is truthy. The retry path is skipped and the call returns an empty list rather than trying a later screenshot. The current main branch at 9d5deaa89520c6e4cec61248f2c0c71931160866 reproduces this using a stubbed screenshot sequence.

Expected behavior

find_all should keep checking screenshots until it finds matches or the configured waiting_time is exhausted.

Steps to Reproduce

1. Call DesktopBot.find_all with a positive waiting_time.
2. Stub get_screenshot to return two images without the target, followed by an image with the target.
3. Observe that main returns [] after the first screenshot instead of finding the later target.

The regression test on existing PR #69 exercises this sequence without a physical screen.

Possible Solution

Materialize the locate_all_opencv generator before checking whether it contains matches, so an empty result continues the wait loop.

My Platform

Observed on repository main at 9d5deaa89520c6e4cec61248f2c0c71931160866; reproduction uses a stubbed screenshot sequence and does not require a physical display. Exact first affected package release is not established.

Additional context

This ticket is being filed to track already-open PR #69, which predates it, and make the contribution issue reference explicit. Issue #50 covers duplicate detections in find_all, not the wait/retry behavior described here.

This contribution was prepared with AI assistance by breken-ai.