* chore: add `trapped_rainwater.cpp` to DIRECTORY.md
* feat: implement Trapped Rain Water algorithm
* chore: add links to the trapped rain water problem
* chore(docs): remove Trapped Rain Water dir
* ref: add edges tests
* doc: adding Sozel as author
* doc: includes documentatino
* ref: use `unsigned int` for height of walls
* fix: use fixed-width integers instead of unsigned int
* chore: rearrange included libraries
---------
Co-authored-by: realstealthninja <68815218+realstealthninja@users.noreply.github.com>