Declare that this repo's release prose is English

The release skill's house style opened with "everything here is written in
Swedish", stated as a house default. It is not one: Swedish belongs to
riksdata and rd-web because their interface copy and the riksdag data they
present are inseparable from it. Nothing about an on-call tool is — the
labels, the API and the data here are English, and so are the code comments
and the docs.

Stated as a rule that was remembered rather than read, it produced the whole
of v0.9.2 in Swedish: four commits, the tag body and both charts PRs. The
PRs were rewritten; the commits on main and the published tag could not be,
so v0.9.2 stays as the record of the mistake.

PROSE_LANG makes it a declaration each repo carries, which release-preflight
prints on the prose line before any of the four texts get written. See
reference/house-style.md in the skill.

Claude-Session: https://claude.ai/code/session_01S7R4gWTz5wh5xCY4nCSJjN

.release.conf

@@ -6,6 +6,7 @@
 # Defaults, set here only where this repo differs:
 #   CHARTS_REPO=$HOME/git/charts   CHARTS_DIR=<image basename>
 #   GITEA_LOGIN=Ryuvia            APPVERSION_PREFIX=
+#   PROSE_LANG=en
 
 # Same as the image basename, so this is only stated to be read rather than derived.
 CHARTS_DIR=terdut-server
@@ -15,3 +16,9 @@ CHARTS_DIR=terdut-server
 # version and appVersion from the tag when it publishes -- but people read it, and until
 # 2026-09-01 it said "latest" while the tree headed for a numbered release.
 APPVERSION_PREFIX=v
+
+# English. The Swedish in riksdata and rd-web follows from their subject matter, not from a
+# house style: terdut-server is an on-call tool whose labels, API and data are English, and
+# nothing about it is coupled to Swedish. Code comments and docs here were always English;
+# from 2026-09-01 the release prose is too.
+PROSE_LANG=en