Proposal for OpenHarmony Adaptation of [ diff-match-patch-cpp-stl ]

# Title: Proposal for OpenHarmony Adaptation of [ diff-match-patch-cpp-stl ] ## Background OpenHarmony is an open-source operating system and community that is widely used in the field of intelligent terminals. Currently, diff-match-patch-cpp-stl is extensively utilized in the mobile application development domain of OpenHarmony. In order to enable diff-match-patch-cpp-stl to support the OpenHarmony system, we have modified some of the code of diff-match-patch-cpp-stl. We plan to submit the modified code to the diff-match-patch-cpp-stl community. The purpose of creating this Issue is to initiate discussions with the community. We sincerely welcome you to put forward your valuable suggestions. ## Adaptation Proposal We have completed the OpenHarmony adaptation for diff-match-patch-cpp-stl, including: - Using OpenHarmony cross-compile tools build diff-match-patch-cpp-stl. - Adding OpenHarmony guide to help developers to use diff-match-patch-cpp-stl. We're willing to make a contribution by adding instructions specific to OpenHarmony for using diff-match-patch-cpp-stl. We will submit the changes via a Pull Request(PR) shortly. ## Testing Results We have conducted extensive compatibility testing across: - DevEco Studio 5.0.3 Release-5.0.9.221, SDK: API15 (OpenHarmony 5.0.3.135) - DevEco Studio 5.0.4 Beta1-5.0.9.320, SDK: API16 (OpenHarmony 5.0.4.150) - DevEco Studio 5.0.3 Release-5.0.9.300, SDK: API15 (OH_SDK 5.0.3.135(SP1)) - DevEco Studio 5.0.4 Beta1 5.0.9.320, SDK: API16 (OH SDK 5.0.4.150) ## Labels compatibility, cross-platform