fix Links in docs

Author: hotzenklotz

docs/ui/toolbar.md

@@ -82,7 +82,7 @@ For detailed information, see the [skeleton annotation guide](../skeleton_annota
 WEBKNOSSOS provides several tools for volume annotation:
 
 ![Trace Tool](./images/trace-tool.jpg){align=left width="60"} 
-**Trace Tool**: Create precise boundary definitions by drawing outlines around structures. This tool is particularly useful when accuracy is crucial. For added precision consider using a [pen input device](../pen_tablets.md). 
+**Trace Tool**: Create precise boundary definitions by drawing outlines around structures. This tool is particularly useful when accuracy is crucial. For added precision consider using a [pen input device](../volume_annotation/pen_tablets.md). 
 
 ![Brush Tool](./images/brush-tool.jpg){align=left width="60"} 
 **Brush Tool**: Paint directly onto the dataset to mark regions of interest. The brush size is adjustable to match your needs. If you draw around objects in one continuous motion, the inside will be filled automatically.

docs/volume_annotation/tools.md

@@ -22,7 +22,7 @@ Volume annotation in WEBKNOSSOS allows you to label and segment 3D structures in
 - Relabeling segments with different IDs/colors
 - Quick corrections of small areas
 - The fill behavior can be modified using the 2D/3D fill modifiers (see below).
-- This tool only takes existing labels into account and does not look at any other underlying (microscopy) layers. Have a look at the [quick-select-tool](./quick_select.md) for quickly annotating new structures.
+- This tool only takes existing labels into account and does not look at any other underlying (microscopy) layers. Have a look at the [quick-select-tool](#quick-select-tool) for quickly annotating new structures.
 
 ![Segment Picker Tool](../ui/images/segment-picker-tool.jpg){align=left width="60"} 
 **Segment Picker**: Click any segment to use its label ID as the active segment ID and keep annotating with that ID. This is alternative to selecting the segment ID from the [Segments list](./segments_list.md) sidebar or context menu.