tools: Export- und Eingangsordner im Backup-Ziel - Überschneidungsregel nur noch auf <ziel>/git und den eigenen Maschinenordner, Laufzeitprüfung auf Vorfahren in upload collect und export run (#216); 10.1.0-beta.16

Files changed:
- CHANGES.md
- VERSION
- docs/how-to/back-up-to-a-synced-folder.md
- docs/how-to/collect-from-a-synced-folder.md
- docs/how-to/export-to-a-synced-folder.md
- docs/reference/commands/exports.md
- docs/reference/commands/raw-material-and-uploads.md
- docs/reference/configuration.md
- tools/CONTRACT.md
- tools/chemenu/backup.py
- tools/chemenu/collect.py
- tools/chemenu/commands/export_cmd.py
- tools/chemenu/commands/upload_cmd.py
- tools/chemenu/config_shapes.py
- tools/chemenu/page_export.py
- tools/chemenu/tests/test_collect.py
- tools/chemenu/tests/test_export_run.py
- tools/chemenu/upload.py

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SnAJ7Z3CpVD3PRbN73QtU2

docs/how-to/export-to-a-synced-folder.md

@@ -38,8 +38,12 @@ look like: [configuration reference](../reference/configuration.md#export-to-a-f
 
 1. **Pick the folder**: a folder inside the synced folder, for example
    `C:\Users\<you>\OneDrive - <company>\Chemenu-Lesefassung`. It must be empty or not exist yet,
-   and it must lie outside the instance, outside every other export target, outside every `intake`
-   folder and outside `backup.target`.
+   and it must lie outside the instance, outside every other export target and every `intake`
+   folder, and apart from the folders the backup writes into: it may not be, lie in or contain
+   `<backup.target>\git` or the backup's machine folder, nor lie in another machine's folder or a
+   bare repository. A folder beside them is fine, so one synced folder can hold the backup, an
+   intake folder and the export, with the export in `<OneDrive - company>\Chemenu\Export`
+   ([the layout](back-up-to-a-synced-folder.md#one-folder-for-the-backup-the-intake-and-the-export)).
 2. **Write the `export` section** into `.wikitool-local.json` at the root of the instance - by hand,
    since its fields decide what leaves this machine and which program runs, and `config set`
    refuses them: