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+# Project Guidelines
+
+## Commits
+Follow GNOME style: Summary <72 chars, imperative, no period. Body with bullet points for changes.
+
+## Code
+- Classes for modularity, private attrs/methods (_prefix).
+- Avoid redundancy (e.g., single strip() calls).
+- Encapsulation over public access.
+
+## Testing
+- Dry-run first, check logs/counts vs. Thunderbird.
+- Verify no duplicates or errors.
+
+## Security
+- Never commit .env; use .env.example.
+- Private credentials, no hard-coded URLs.
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