diff --git a/.editorconfig b/.editorconfig
index f517e5c..1a1f9ab 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -1,5 +1,27 @@
+# EditorConfig
+# https://editorconfig.org/
+#
+# Consistent formatting for project files.
+
 root = true
 
+[*]
+end_of_line = lf
+insert_final_newline = true
+
+[*.{php,js,css,json,html,htm,txt,md,yml,yaml,xml,twig}]
+charset = utf-8
+indent_style = tab
+indent_size = 4
+trim_trailing_whitespace = true
+
+[*.{txt,md,yml,yaml}]
+trim_trailing_whitespace = false
+
+[*.{yml,yaml}]
+indent_style = space
+
+# Existing project-specific settings
 [*]
 charset = utf-8
 end_of_line = lf
@@ -14,3 +36,7 @@ indent_size = 4
 
 [*.md]
 trim_trailing_whitespace = false
+
+# YAML requires spaces rather than tabs.
+[*.{yml,yaml}]
+indent_style = space
diff --git a/.gitattributes b/.gitattributes
index 8b106ef..bdc1a72 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -1,6 +1,8 @@
-# Normalize line endings to LF in the repository
+# Shared line endings and binary files
 * text=auto eol=lf
 
+# Normalize line endings to LF in the repository
+
 # Never convert line endings in binary files
 *.png binary
 *.jpg binary
diff --git a/.gitignore b/.gitignore
index d2a29da..0d450d9 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,121 @@
-# Generated by proteus_hugo.sh — not source, regenerate from
-# proteus_doc_<lang>.xml instead of tracking the built output.
+# =========================
+# Build and Dependencies
+# =========================
+
+/build/
+/vendor/
+
+# =========================
+# Ghostwriter
+# =========================
+
+# Ghostwriter backup markdown files
+*.md.backup
+
+# =========================
+# Windows
+# =========================
+
+# Windows image file caches
+Thumbs.db
+ehthumbs.db
+
+# Folder configuration file
+Desktop.ini
+
+# Recycle Bin used on file shares
+$RECYCLE.BIN/
+
+# =========================
+# macOS
+# =========================
+
+.DS_Store
+.AppleDouble
+.LSOverride
+
+# Custom folder icons
+Icon?
+
+# Thumbnails
+._*
+
+# Files that might appear on external disks
+.Spotlight-V100
+.Trashes
+
+# Directories potentially created on remote AFP shares
+.AppleDB
+.AppleDesktop
+Network Trash Folder
+Temporary Items
+.apdisk
+
+# =========================
+# PHP / Composer
+# =========================
+
+vendor
+composer.phar
+
+# =========================
+# Python
+# =========================
+
+__pycache__/
+*.py[cod]
+.venv/
+venv/
+.pytest_cache/
+.mypy_cache/
+.ruff_cache/
+.tox/
+.nox/
+.coverage
+.coverage.*
+htmlcov/
+
+# =========================
+# JavaScript / Node
+# =========================
+
+node_modules/
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+.pnpm-debug.log*
+
+# =========================
+# Local environment and editor files
+# =========================
+
+.env
+.env.*
+!.env.example
+!.env.*.example
+*~
+*.backup
+*.bk
+*.bak
+*.swp
+*.swo
+
+# =========================
+# Local review output
+# =========================
+
+output*.txt
+*-review-*.md
+
+# IDE files
+.idea/
+*.iws
+.idea_modules/
+atlassian-ide-plugin.xml
+/nbproject/
+
+# Repository-specific rules
+# Generated documentation; retain the tracked directory placeholders.
 /docs-build/*
 !/docs-build/.gitkeep
 !/docs-build/.htaccess