add attribution for self host instance

docker/attribution/de.json

@@ -0,0 +1,3 @@
+{
+	"pages.attribution.self-hosted": "Self-Hosted-Version von Adventure Land.<br>Original &amp; Lizenz: <a target=\"_blank\" rel=\"noopener\" class=\"cancela eexternal\" style=\"display: inline; color: #33BF6D\" href=\"https://adventure.land\">adventure.land</a><br>Kein Support durch das Originalprojekt."
+}

docker/attribution/en.js

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+// Self-host attribution line, copied into /app/languages/en/ at image build.
+//
+// The license of Adventure Land requires a crawlable link back to
+// https://adventure.land and forbids implying that the original project
+// supports a self-hosted instance. docker/patch-attribution.js points the
+// login/selection help box at this phrase instead of the upstream
+// "Email, for anything" line.
+//
+// English is also the fallback for every language without its own
+// attribution.json, so keep the markup identical to docker/attribution/de.json.
+module.exports = {
+	"pages.attribution.self-hosted":
+		'Self-hosted version of Adventure Land.<br>Original &amp; license: <a target="_blank" rel="noopener" class="cancela eexternal" style="display: inline; color: #33BF6D" href="https://adventure.land">adventure.land</a><br>No support by the original project.',
+};

docker/patch-attribution.js

@@ -0,0 +1,55 @@
+#!/usr/bin/env node
+// Local patch: self-host attribution box (applied at image build time).
+//
+// The AdventureLandOnlyUse license requires a crawlable link back to
+// https://adventure.land, and the original project should not appear to
+// support a self-hosted instance. The upstream login/character-selection help
+// box (htmls/contents/account_help.html) shows "Email, for anything:
+// hello@adventure.land" from a phrase. This patch points that component at
+// pages.attribution.self-hosted instead, which ships as
+// docker/attribution/{en.js,de.json}; all other languages fall back to English.
+//
+// The script fails loudly when the upstream phrase is gone or the shipped
+// catalog is incomplete, so a code update cannot silently drop the attribution.
+
+const fs = require("node:fs");
+const path = require("node:path");
+
+const template = process.argv[2] || "/app/htmls/contents/account_help.html";
+const app = path.resolve(path.dirname(template), "..", "..");
+
+const upstream_id = "pages.contents.selection_features.email-for-anything-hello-adventure-land";
+const phrase_id = "pages.attribution.self-hosted";
+const license_url = "https://adventure.land";
+
+function fail(message) {
+	console.error("patch-attribution: " + message);
+	process.exit(1);
+}
+
+const catalogs = [
+	["en", require(path.join(app, "languages", "en", "attribution.js"))],
+	["de", JSON.parse(fs.readFileSync(path.join(app, "languages", "de", "attribution.json"), "utf8"))],
+];
+
+for (const [language, catalog] of catalogs) {
+	const text = catalog[phrase_id];
+	if (typeof text !== "string") fail("missing " + phrase_id + " in languages/" + language + "/attribution");
+	if (!text.includes('href="' + license_url + '"')) {
+		fail("languages/" + language + "/attribution does not link to " + license_url);
+	}
+}
+
+const source = fs.readFileSync(template, "utf8");
+
+if (source.includes('"' + phrase_id + '"')) {
+	console.log("patch-attribution: already applied");
+	process.exit(0);
+}
+
+if (source.split(upstream_id).length !== 2) {
+	fail("expected exactly one occurrence of " + upstream_id + " in " + template);
+}
+
+fs.writeFileSync(template, source.replace(upstream_id, phrase_id));
+console.log("patch-attribution: applied to " + template);