## Summary of Changes
This PR fixes various typos across multiple packages. The changes
include:
* **Variable Names:** Corrected local variable names (e.g.,
`list_lenght` → `list_length`, `inital_nb_pts` → `initial_nb_pts`) in
CMake scripts and C++ headers.
* **Header Guards:** Fixed a typo in the header guard for
`Edge_length_cost.h` to match the filename.
* **Documentation & Comments:** Fixed spelling errors in comments,
string literals, and documentation files (e.g., `dimensionnal` →
`dimensional`, `explicitelty` → `explicitly`).
## Release Management
* Affected package(s): Installation, Point_set_3,
Polygon_mesh_processing, Surface_mesh_simplification, SMDS_3,
STL_Extension, Stream_support, TDS_2, Triangulation_2, Triangulation_3
* Issue(s) solved (if any):
* Feature/Small Feature (if any):
* Link to compiled documentation (obligatory for small feature):
* License and copyright ownership: