fix: point source links and instance fetch at this fork

Upstream references still pointed at git.macaw.me, which is unmaintained
and whose instances.json is a dead link. Repoint them at this repo:

- RefreshInstances now fetches instances.json from raw.githubusercontent
- source/version links in index.htm, about.htm, and CLI help use the
  GitHub releases tag URL
- SETUP.md/SETUP-RU.md language switch links were Gitea-absolute paths
  that 404 on GitHub; make them relative
- --add-instance message says 'main' branch, matching this repo

The fork attribution in README.md is left as-is: it credits upstream
rather than pointing at the source.

1 files changed, 1 insertions, 1 deletions

diff --git a/SETUP.md b/SETUP.md
index cc89118..456318c 100755
--- a/SETUP.md
+++ b/SETUP.md
@@ -1,4 +1,4 @@
-[Версия на русском языке 🇷🇺](/skunky/SkunkyArt/src/branch/master/SETUP-RU.md)
+[Версия на русском языке 🇷🇺](SETUP-RU.md)
 
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