Stop rendering the DocumentCenter as a blank page

Both the prose-documents and work-products sections rendered as
`{x.length > 0 ? ... : null}` with no else branch, and the whole
DocumentCenter was only mounted when a company was selected. The
combined result: a company with no files gave the operator a page
containing only a title and a "New" button, and an operator who had
not yet picked a company saw nothing at all — the exact "page is blank
even though docs were generated" complaint.

Add an explicit empty state inside DocumentCenter (surfaced only when
both collections are empty) and a separate "select a company" empty
state at the section router level. Strings live in the i18n bundle so
the Chinese locale is not left behind.

src/renderer/components/company-operations/DocumentCenter.tsx

@@ -1,7 +1,7 @@
 import { useMemo, useState } from "react";
-import { FileText, FloppyDisk, NotePencil, Trash } from "../ui/icons";
+import { FileText, FloppyDisk, NotePencil, Plus, Trash } from "../ui/icons";
 import type { AgentRecord, DocumentRecord, GoalRecord, ProjectRecord, WorkProductRecord } from "@shared/types";
-import { ActionButton, ConfirmDialog, InlineNotice, Input, ListFrame, ListRow, Modal, Select, StatusPill, TextArea } from "../ui";
+import { ActionButton, ConfirmDialog, EmptyState, InlineNotice, Input, ListFrame, ListRow, Modal, Select, StatusPill, TextArea } from "../ui";
 import { useT } from "../../i18n";
 import { documentTypeOptions, documentStatusOptions, splitTags, parseTags } from "./helpers";
 import { SectionHeader } from "./SectionHeader";
@@ -120,10 +120,18 @@ export function DocumentCenter({ companyId, documents, workProducts, agents, pro
   const activeDocument = useMemo(() => documents.find((document) => document.id === editingId) ?? null, [documents, editingId]);
 
   const totalCount = documents.length + workProducts.length;
+  const isEmpty = totalCount === 0;
 
   return (
     <div>
       <SectionHeader title={t("ops.documentCenter")} count={totalCount} action={() => setEditingId(NEW_ENTITY_ID)} />
+      {isEmpty ? (
+        <EmptyState
+          title={t("ops.documentsEmptyTitle")}
+          detail={t("ops.documentsEmptyDetail")}
+          action={<ActionButton label={t("ops.documentsEmptyAction")} icon={Plus} tone="accent" onClick={() => setEditingId(NEW_ENTITY_ID)} />}
+        />
+      ) : null}
       {documents.length > 0 ? (
         <div>
           <div className="px-4 pt-3 pb-1 text-[11px] font-medium uppercase tracking-wide text-muted-foreground">

src/renderer/i18n/en.ts

@@ -873,6 +873,10 @@ export const en: Record<string, string> = {
   "ops.documentCenter": "Document Center",
   "ops.documentsProse": "Prose documents",
   "ops.documentsWorkProducts": "Files & deliverables",
+  "ops.documentsEmptyTitle": "No documents yet",
+  "ops.documentsEmptyDetail": "Agents register files here automatically when they write to the workspace, and can publish prose documents (PRDs, specs, post-mortems) via POST /api/companies/{id}/documents.",
+  "ops.documentsEmptyAction": "Create the first document",
+  "ops.documentsSelectCompany": "Select a company from the workspace switcher to see its documents.",
   "ops.knowledgeBase": "Knowledge Base",
   "ops.meetings": "Meetings",
   "ops.sprintBoard": "Sprint Board",

src/renderer/i18n/zh.ts

@@ -873,6 +873,10 @@ export const zh: Record<string, string> = {
   "ops.documentCenter": "文档中心",
   "ops.documentsProse": "文稿",
   "ops.documentsWorkProducts": "文件与交付物",
+  "ops.documentsEmptyTitle": "还没有文档",
+  "ops.documentsEmptyDetail": "Agent 在 workspace 里写文件时会被自动登记为交付物；结构化文稿（PRD、技术规格、复盘）需要调用 POST /api/companies/{id}/documents 发布。",
+  "ops.documentsEmptyAction": "创建第一份文档",
+  "ops.documentsSelectCompany": "请先在工作区切换器中选择一家公司，才能查看它的文档。",
   "ops.knowledgeBase": "知识库",
   "ops.meetings": "会议",
   "ops.sprintBoard": "迭代看板",

src/renderer/views/sections/OperationsSections.tsx

@@ -18,7 +18,8 @@ import { DocumentCenter } from "../../components/company-operations/DocumentCent
 import { KnowledgeBaseManager } from "../../components/company-operations/KnowledgeBaseManager";
 import { MeetingsManager } from "../../components/company-operations/MeetingsManager";
 import { SprintManager } from "../../components/company-operations/SprintManager";
-import { Panel } from "../../components/ui";
+import { EmptyState, Panel } from "../../components/ui";
+import { useT } from "../../i18n";
 import { unwrap } from "../../lib/desktop";
 import { useAppStore } from "../../state/store";
 import { useSectionContext } from "../../hooks/useSectionContext";
@@ -29,6 +30,7 @@ interface OperationsSectionsProps {
 }
 
 export function OperationsSections({ section }: OperationsSectionsProps) {
+  const t = useT();
   const {
     snapshot,
     currentCompany,
@@ -212,16 +214,23 @@ export function OperationsSections({ section }: OperationsSectionsProps) {
         />
       ) : null}
 
-      {section === "documents" && currentCompany ? (
-        <DocumentCenter
-          companyId={currentCompany.id}
-          documents={companyDocuments}
-          workProducts={companyWorkProducts}
-          agents={companyAgents}
-          projects={companyProjects}
-          goals={companyGoals}
-          onRefresh={refresh}
-        />
+      {section === "documents" ? (
+        currentCompany ? (
+          <DocumentCenter
+            companyId={currentCompany.id}
+            documents={companyDocuments}
+            workProducts={companyWorkProducts}
+            agents={companyAgents}
+            projects={companyProjects}
+            goals={companyGoals}
+            onRefresh={refresh}
+          />
+        ) : (
+          <EmptyState
+            title={t("ops.documentsEmptyTitle")}
+            detail={t("ops.documentsSelectCompany")}
+          />
+        )
       ) : null}
 
       {section === "knowledge" && currentCompany ? (