[master] 8f9010fba doc: Add generic process to CONTRIBUTING

[Nils Goroll]

commit 8f9010fba70c2744042ace579f003ab45330865b
Author: Nils Goroll <nils.goroll at uplex.de>
Date:   Tue May 27 16:44:54 2025 +0200

    doc: Add generic process to CONTRIBUTING
    
    As agreed at vdd25q2

diff --git a/CONTRIBUTING b/CONTRIBUTING
index f15022d2d..8ba7471d3 100644
--- a/CONTRIBUTING
+++ b/CONTRIBUTING
@@ -20,6 +20,16 @@ through new (and old) tickets.  It speeds things up a lot if you
 can join the channel and answer questions directly when we go over
 the ticket.
 
+General process
+---------------
+
+In general, please follow these steps when contributing new features or
+non-trivial fixes:
+
+1) Present the idea on -dev or in an issue
+2) Write the documentation and present it
+3) Create the full PR
+
 GitHub pull requests
 --------------------