fix(migrations): judge each German field on its own in migration 195

repairGerman gated subject, body_html and body_text on body_html alone, the
same defect Codex found in migration 194: an admin who had translated only
the subject lost it the moment the HTML still matched English, and down()
is a deliberate no-op, so the loss was unrecoverable. Each field is now
judged independently for both the translations row and the legacy _de
columns, matching 194's corrected pattern. Two tests pin the two
directions (translated subject over English body, and the reverse).

backend/__tests__/migrations/195_german_gallery_lifecycle_templates.test.js

@@ -203,6 +203,35 @@ describe('migration 195 — German + seeding for the remaining gallery-lifecycle
 
       expect((await rowFor(id, 'de')).body_html).toContain('Galerie läuft bald ab');
     });
+
+    it('keeps a subject the admin translated while repairing the still-English body', async () => {
+      // Each field is judged on its own. Gating on body_html alone would have
+      // thrown this subject away — and down() is a no-op, so for good.
+      const adminSubject = 'Nur noch kurz: Ihre Galerie läuft ab';
+      const id = await seedFreshInstall({ deSubject: adminSubject });
+
+      await migration.up(knex);
+
+      const de = await rowFor(id, 'de');
+      expect(de.subject).toBe(adminSubject);
+      expect(de.body_html).toContain('Galerie läuft bald ab');
+      expect(de.body_text).toContain('Tagen ab');
+      const master = await masterFor('expiration_warning');
+      expect(master.subject_de).toBe(adminSubject);
+      expect(master.body_html_de).toContain('Galerie läuft bald ab');
+    });
+
+    it('keeps an admin-translated body while repairing a still-English subject', async () => {
+      const adminHtml = '<p>Hallo {{host_name}}, in {{days_remaining}} Tagen ist Schluss: {{gallery_link}} ({{event_name}})</p>';
+      const id = await seedFreshInstall({ deHtml: adminHtml });
+
+      await migration.up(knex);
+
+      const de = await rowFor(id, 'de');
+      expect(de.body_html).toBe(adminHtml);
+      expect(de.subject).toBe('Ihre Fotogalerie läuft bald ab');
+      expect((await masterFor('expiration_warning')).body_html_de).toBe(adminHtml);
+    });
   });
 
   describe.each([

backend/migrations/core/195_german_gallery_lifecycle_templates.js

@@ -27,11 +27,12 @@
  *
  * This migration therefore does two things, both conservative:
  *
- *   - REPAIR: rewrite a German row (and the legacy `_de` columns) only while
- *     it is still byte-identical to the English one, or empty. That is
- *     precisely the broken state. A legacy install whose German came from
- *     migration 026, or any install where an admin edited the template, is
- *     left untouched.
+ *   - REPAIR: rewrite a German field (and the legacy `_de` columns) only
+ *     while it is still byte-identical to the English one, or empty. That is
+ *     precisely the broken state. Each of subject / body_html / body_text is
+ *     judged on its own, so a legacy install whose German came from migration
+ *     026, or any install where an admin edited even one field, keeps what it
+ *     has.
  *   - SEED: insert `gallery_expired` / `archive_complete` with EN + DE only
  *     when the master row is missing entirely. Never overwrites an existing
  *     row.
@@ -163,7 +164,9 @@ async function repairGerman(knex, templateKey, german, now) {
       .where({ template_id: master.id, language: 'de' })
       .first();
 
+    const englishSubject = (enRow && enRow.subject) || master.subject_en || master.subject || '';
     const englishHtml = (enRow && enRow.body_html) || master.body_html_en || master.body_html || '';
+    const englishText = (enRow && enRow.body_text) || master.body_text_en || master.body_text || '';
 
     if (!deRow) {
       await knex('email_template_translations').insert({
@@ -175,30 +178,41 @@ async function repairGerman(knex, templateKey, german, now) {
         created_at: now,
         updated_at: now,
       });
-    } else if (isUntranslated(deRow.body_html, englishHtml)) {
-      await knex('email_template_translations')
-        .where({ id: deRow.id })
-        .update({
-          subject: german.subject,
-          body_html: german.body_html,
-          body_text: german.body_text,
-          updated_at: now,
-        });
+    } else {
+      // Each field is judged on its own, as in migration 194. Gating all three
+      // on body_html would overwrite a subject the admin had already translated
+      // whenever the HTML still matched English — and down() is a deliberate
+      // no-op, so that loss would be unrecoverable.
+      const patch = {};
+      if (isUntranslated(deRow.subject, englishSubject)) patch.subject = german.subject;
+      if (isUntranslated(deRow.body_html, englishHtml)) patch.body_html = german.body_html;
+      if (isUntranslated(deRow.body_text, englishText)) patch.body_text = german.body_text;
+      if (Object.keys(patch).length > 0) {
+        patch.updated_at = now;
+        await knex('email_template_translations').where({ id: deRow.id }).update(patch);
+      }
     }
   }
 
   // Legacy per-language columns on the master row — still the fallback path in
   // emailProcessor.processTemplate when the translations table is unavailable.
   const cols = await knex('email_templates').columnInfo();
-  if (cols.body_html_de && isUntranslated(master.body_html_de, master.body_html_en)) {
-    await knex('email_templates')
-      .where({ id: master.id })
-      .update({
-        subject_de: german.subject,
-        body_html_de: german.body_html,
-        body_text_de: german.body_text,
-        updated_at: now,
-      });
+  if (cols.body_html_de) {
+    // Same per-field rule as the translations table above.
+    const legacyPatch = {};
+    if (cols.subject_de && isUntranslated(master.subject_de, master.subject_en)) {
+      legacyPatch.subject_de = german.subject;
+    }
+    if (isUntranslated(master.body_html_de, master.body_html_en)) {
+      legacyPatch.body_html_de = german.body_html;
+    }
+    if (cols.body_text_de && isUntranslated(master.body_text_de, master.body_text_en)) {
+      legacyPatch.body_text_de = german.body_text;
+    }
+    if (Object.keys(legacyPatch).length > 0) {
+      legacyPatch.updated_at = now;
+      await knex('email_templates').where({ id: master.id }).update(legacyPatch);
+    }
   }
   return true;
 }