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imgproc: accept CV_Bool masks in matchTemplate (#25895) - #29677 ### Problem `cv::Mat_<bool>::depth()` returns `CV_Bool` in 5.0, where it returned `CV_8U` in 4.x. `matchTemplateMask` gates the mask at `templmatch.cpp:737`, so passing a boolean mask now fails with: ``` (-215:Assertion failed) _mask.depth() == CV_8U || _mask.depth() == CV_32F in function 'cv::matchTemplateMask' ``` A binary mask is a normal input for masked template matching, so this is a regression against 4.x. ### Fix Allow `CV_Bool` in the assertion and widen the mask to `CV_8U` before the existing binarization step. The widening is required rather than passing `CV_Bool` straight through, because `cv::threshold()` does not accept `CV_Bool`. Once widened, the existing `THRESH_BINARY` path treats any non-zero entry as selected, which is exactly the documented `CV_8U` mask semantics. `CV_8U` and `CV_32F` masks take an unchanged path. The masked path is the only one affected: `cv::matchTemplate` routes every non-empty mask through `matchTemplateMask`, and there is no OpenCL mask variant. ### Test `Imgproc_MatchTemplateBoolMask.matches_uchar_mask` compares a `Mat_<bool>` mask against the equivalent `CV_8UC1` mask and requires the results to agree, across all six match methods (`TM_SQDIFF`, `TM_SQDIFF_NORMED`, `TM_CCORR`, `TM_CCORR_NORMED`, `TM_CCOEFF`, `TM_CCOEFF_NORMED`) for `CV_8UC1`, `CV_8UC3` and `CV_32FC1` images. 18 parameter combinations. Verified locally on 5.x: all 18 fail without the source change (with the assertion above) and pass with it. The full `*MatchTemplate*` set, 165 tests, passes. No test data needed, the test is synthetic. Part of #25895, and follows the same approach as #29580, #29597 and #29622. ### Pull Request Readiness Checklist - [x] I agree to contribute to the project under Apache 2 License. - [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV - [x] The PR is proposed to the proper branch - [x] There is a reference to the original bug report and related work - [x] There is accuracy test, performance test and test data in opencv_extra repository, if applicable Patch to opencv_extra has the same branch name. - [x] The feature is well documented and sample code can be built with the project CMake