v0.247.0: i18n spike — the dashboard can speak English, Hungarian byte-identical

Message bundles (internal/i18n) expanded into templates before parsing, one
template set per language. Launcher, /backups, /apps/<slug> and the layout
converted; household language setting, POST /settings/language, ?lang= override,
report field. Parity test against fixtures captured from unconverted templates;
copy gates read templates expanded; new i18n_missing_gate.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0159rPz1ZhFKsS53msqPYxtS

controller/scripts/i18n_bundle.py

@@ -0,0 +1,48 @@
+# -*- coding: utf-8 -*-
+"""i18n_bundle.py -- read a dashboard template the way the controller renders it.
+
+Since v0.247.0 a template's copy lives in internal/i18n/locales/<lang>.json and the template carries
+`{{T "key"}}` markers, expanded before parsing (internal/i18n/i18n.go). A gate that reads the raw
+template no longer sees that copy -- the retrieval-promise gate went STALE the moment the first page
+was converted, which is how this module was found to be needed. Gates that judge copy, markup or
+template actions call expand()/read_template() so they judge what a household actually receives, in
+every language.
+
+The marker pattern is the Go one, character for character (markerRe); an undefined key is left in
+place, exactly as the loader leaves it.
+"""
+import io
+import json
+import os
+import re
+
+_HERE = os.path.dirname(os.path.abspath(__file__))
+LOCALES = os.path.join(_HERE, "..", "internal", "i18n", "locales")
+LANGS = ("hu", "en")
+MARKER = re.compile(r'\{\{\s*T\s+"([A-Za-z0-9_.\-]+)"\s*\}\}')
+
+_cache = {}
+
+
+def load(lang):
+    if lang not in _cache:
+        p = os.path.join(LOCALES, lang + ".json")
+        _cache[lang] = json.load(io.open(p, encoding="utf-8")) if os.path.exists(p) else {}
+    return _cache[lang]
+
+
+def expand(text, lang):
+    hu, own = load("hu"), load(lang)
+
+    def rep(m):
+        k = m.group(1)
+        if k in own:
+            return own[k]
+        if k in hu:
+            return hu[k]
+        return m.group(0)
+    return MARKER.sub(rep, text)
+
+
+def read_template(path, lang="hu"):
+    return expand(io.open(path, encoding="utf-8").read(), lang)