docs/geek: Add TOS 3.x migration guide

4 jobs for 3x-migration in 1 minute and 57 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Test
passed #397151
test-compilation

00:00:34

passed #397152
test-links

00:00:39

passed #397153
test-remote-links

00:01:23

 
  Build
passed #397154
build

00:00:34