Add docs for file processing

website/site/content/docs/tools/convert-all-pdf.md

@@ -46,6 +46,6 @@ There will be one task per file to convert. All these tasks are
 submitted with a low priority. So files uploaded through the webapp or
 a [source](@/docs/webapp/uploading.md#anonymous-upload) with a high
 priority, will be preferred as [configured in the job
-executor](@/docs/joex/_index.md#scheduler-config). This is to not
+executor](@/docs/joex/intro.md#scheduler-config). This is to not
 disturb normal processing when many conversion tasks are being
 executed.

website/site/content/docs/tools/regenerate-previews.md

@@ -0,0 +1,42 @@
++++
+title = "Regenerate Preview Images"
+description = "Re-generates all preview images."
+weight = 80
++++
+
+# regenerate-previews.sh
+
+This is a simple bash script to trigger the endpoint that submits task
+for generating preview images of your files. This is usually not
+needed, but should you change the `preview.dpi` setting in joex'
+config file, you need to regenerate the images to have any effect.
+
+# Requirements
+
+It is a bash script that additionally needs
+[curl](https://curl.haxx.se/) and
+[jq](https://stedolan.github.io/jq/).
+
+# Usage
+
+```
+./regenerate-previews.sh [docspell-base-url]
+```
+
+For example, if docspell is at `http://localhost:7880`:
+
+```
+./convert-all-pdfs.sh http://localhost:7880
+```
+
+The script asks for your account name and password. It then logs in
+and triggers the said endpoint. After this you should see a few tasks
+running.
+
+There will be one task per file to convert. All these tasks are
+submitted with a low priority. So files uploaded through the webapp or
+a [source](@/docs/webapp/uploading.md#anonymous-upload) with a high
+priority, will be preferred as [configured in the job
+executor](@/docs/joex/intro.md#scheduler-config). This is to not
+disturb normal processing when many conversion tasks are being
+executed.