Subject: Update .gitignore from Debian packaging branch

The Debian packaging git branch contains these updates to the upstream
.gitignore file(s).  This patch is autogenerated, to provide these
updates to users of the official Debian archive view of the package.

[dgit (17.0) update-gitignore]
---
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..5cf6ba4
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,55 @@
+# pcaff runtime artifacts
+sign/
+signed/
+rejected/
+incoming/
+unsigned/
+unsent/
+sent/
+pcaff-extract/
+pcaffremote*
+
+# Python bytecode and caches
+__pycache__/
+*.py[cod]
+*$py.class
+
+# Virtual environments and local environment files
+.venv/
+venv/
+env/
+.env
+.env.*
+!.env.example
+
+# Packaging
+build/
+dist/
+*.egg-info/
+.eggs/
+.pybuild/
+
+# Debian package build state
+debian/.debhelper/
+debian/debhelper-build-stamp
+debian/files
+debian/pcaff/
+debian/*.debhelper
+debian/*.debhelper.log
+debian/*.substvars
+
+# Tests and coverage
+.pytest_cache/
+.coverage
+.coverage.*
+htmlcov/
+
+# Linters and type checkers
+.mypy_cache/
+.pyright/
+.ruff_cache/
+
+# Editors and operating systems
+.idea/
+.vscode/
+.DS_Store
