Postgresql - Snap intersecting and broken MultiLineString

Im trying to use Postgresql to fix a few thousand hiking trails that i have in a map source. Now i have all of the trail parts as MultiLineString but my issue is that each of the trails are broken into multiple MultiLineStrings. Some of them seme to intersect at the point between the lines but some are broken so that there might be a few meters between the lines, i would like to set a tolerance for what distance is allowed between the end of the lines for them to be joined. In total i now have 57000 lines that i need to process. How can i solve this with Postgresql?

Example of intersecting line that is broken:

Example of line that is broken with space between the lines: