Fix file naming conflict error in schemas-md on macOS APFS (case-insensitive)

[mrueda]

In our schemas, there are terms with similar names that only differ in their casing, which leads to the generation of markdown files like:

• AgeRange.md
• ageRange.md
• Value.md
• value.md

This presents issues on case-insensitive filesystems (such as macOS APFS in its case-insensitive configuration).

To resolve this issue, I modified the parsing script. Now, the files are named distinctly to avoid conflicts:

• AgeRange.md has been renamed to AgeRange_PXF.md
• Value.md has been renamed to Value_PXF.md

Additionally, all links to these files have been updated accordingly.