chore: add Codex project context and agent guidance

.agents/skills/kst4contest-documentation/references/release-communications.md

@@ -0,0 +1,35 @@
+# Release communications
+
+## Changelog
+
+Write concise English change descriptions.
+
+Prioritize:
+
+- behaviour users notice;
+- contest workflow impact;
+- protocol/integration compatibility;
+- bug/reliability fixes;
+- documentation improvements.
+
+Avoid internal refactor trivia unless it materially changes reliability or maintainability relevant to the release.
+
+## Social release post
+
+Use `$praktimarc-writing-style`.
+
+Typical structure:
+
+- version;
+- short statement of what the release contains;
+- compact highlights;
+- operational context where relevant, e.g. preparation for a VUSHF contest or planned use at DM5M;
+- one clear download/manual destination.
+
+Do not oversell.
+
+## Download/manual direction
+
+Marc has preferred routing users to the HamRadioOnline/KST4Contest download/manual pages rather than scattering multiple download links.
+
+Before publishing new text, inspect the current website URLs and release setup instead of copying an old link.