replace mkdocs references

Author: igorbenav

.gitignore

@@ -110,7 +110,7 @@ venv.bak/
 # Rope project settings
 .ropeproject
 
-# mkdocs documentation
+# zensical documentation
 /site
 
 # mypy

docs/user-guide/project-structure.md

@@ -7,7 +7,7 @@ The codebase follows a three-layer architecture (**interfaces / infrastructure /
 ```text
 fastapi-boilerplate/
 ├── backend/                  # Python project root (see below)
-├── docs/                     # mkdocs documentation
+├── docs/                     # zensical documentation
 ├── .github/                  # CI workflows
 ├── README.md
 └── LICENSE.md