mAi: #113 - fix admin rules list 'undefined' proceeding name

ProceedingType TS interface in admin-rules-list.ts and admin-rules-edit.ts
declared `name_de` but the Go ProceedingType model serialises `db:"name"`
as JSON key `name` (DE is the primary on the wire). Result: `pt.name_de`
was undefined for every row, so `${pt.code} · ${pt.name_de}` produced the
literal "upc.apl.cost · undefined" in the list (and the same in proceeding
selects of the edit page).

Frontend-only fix:
- Rename the field to `name` to match the API contract.
- Guard the label builder: if the active-language name is missing, fall
  back to just the proceeding code rather than rendering "code · " (or
  worse, the original "code · undefined" string).

Other admin pages that fetch /api/proceeding-types-db (deadlines-new,
deadlines-detail, project-form, fristenrechner) already read `pt.name`
correctly, so the bug was scoped to these two files. TriggerEvent's
`name_de` field is real and stays untouched.

frontend/src/client/admin-rules-edit.ts

@@ -51,7 +51,10 @@ interface Rule {
 interface ProceedingType {
   id: number;
   code: string;
-  name_de: string;
+  // `name` is the German display name on the wire; the Go `ProceedingType`
+  // model serialises `db:"name"` as JSON key `name`. Don't reach for
+  // `name_de` — that field does not exist in this payload (m/paliad#113).
+  name: string;
   name_en: string;
 }
 
@@ -169,7 +172,8 @@ function fillProceedingSelect(selectId: string, list: ProceedingType[]) {
   for (const pt of list) {
     const opt = document.createElement("option");
     opt.value = String(pt.id);
-    opt.textContent = `${pt.code} · ${getLang() === "en" ? pt.name_en : pt.name_de}`;
+    const name = getLang() === "en" ? pt.name_en : pt.name;
+    opt.textContent = name ? `${pt.code} · ${name}` : pt.code;
     sel.appendChild(opt);
   }
 }

frontend/src/client/admin-rules-list.ts

@@ -29,7 +29,11 @@ interface Rule {
 interface ProceedingType {
   id: number;
   code: string;
-  name_de: string;
+  // `name` is the German display name on the wire; the Go `ProceedingType`
+  // model serialises `db:"name"` as JSON key `name` (the schema treats DE
+  // as primary). EN lives in `name_en`. Don't reach for `name_de` — that
+  // field does not exist in this payload (cf. m/paliad#113).
+  name: string;
   name_en: string;
   category: string;
 }
@@ -125,7 +129,12 @@ function proceedingLabel(id: number | null | undefined): string {
   if (id == null) return "—";
   const pt = proceedings.find((p) => p.id === id);
   if (!pt) return `#${id}`;
-  const name = getLang() === "en" ? pt.name_en : pt.name_de;
+  const name = getLang() === "en" ? pt.name_en : pt.name;
+  // Guard against a proceeding row that's missing the active-language
+  // name (or against a stale field-name mismatch slipping back in).
+  // Show the code on its own rather than "code · undefined" — that
+  // literal string is the smell that surfaced this bug (m/paliad#113).
+  if (!name) return pt.code;
   return `${pt.code} · ${name}`;
 }
 
@@ -153,7 +162,8 @@ async function loadProceedings(): Promise<void> {
   for (const pt of proceedings) {
     const opt = document.createElement("option");
     opt.value = String(pt.id);
-    opt.textContent = `${pt.code} · ${getLang() === "en" ? pt.name_en : pt.name_de}`;
+    const name = getLang() === "en" ? pt.name_en : pt.name;
+    opt.textContent = name ? `${pt.code} · ${name}` : pt.code;
     sel.appendChild(opt);
   }
 }