See comment in PR https://github.com/alire-project/alire-index/pull/1804 for LEA:
"Using [gpr-set-externals] here will make the build modes impossible to override by users. Use a default in the GPR file by using External (<VAR>, <default>)."
* Create texcad-4.5.2.toml
First presence of TeXCAD on Alire!
* Update texcad-4.5.2.toml
Correct license naming.
* Update texcad-4.5.2.toml
Enriched the tag list.