feat: add Copyright Act data and OpenGIKAI cross-link (#1, #2)

- Add 著作権法 (Copyright Act) diff data, timeline, AI annotations,
  proposer info, and law summary (closes #2)
- Add OpenGIKAI cross-link component with static mapping file
  (partial progress on #1)
- Show OpenGIKAI thread links in law page sidebar when available
- Add 著作権・創作 life theme
- Update sitemap

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: wharfe

frontend/app/law/[lawId]/page.tsx

@@ -1,8 +1,9 @@
 import type { Metadata } from "next";
 import Link from "next/link";
-import { getTimelineIds, getTimelineData } from "@/lib/data";
+import { getTimelineIds, getTimelineData, getOpenGikaiLinks } from "@/lib/data";
 import { Timeline } from "@/components/timeline";
 import { Icon } from "@/components/icon";
+import { OpenGikaiLinks } from "@/components/opengikai-link";
 import { getThemesForLaw } from "@/lib/life-themes";
 import { BreadcrumbJsonLd } from "@/components/breadcrumb-jsonld";
 
@@ -36,6 +37,7 @@ export default async function LawPage({
   const { lawId } = await params;
   const data = getTimelineData(lawId);
   const themes = getThemesForLaw(lawId);
+  const gikaiLinks = getOpenGikaiLinks(lawId);
 
   return (
     <div className="flex flex-col gap-6">
@@ -158,9 +160,11 @@ export default async function LawPage({
           </div>
         </div>
 
-        {/* Sidebar — Contributors */}
-        {data.contributors && data.contributors.length > 0 && (
-          <div className="lg:w-[260px] shrink-0">
+        {/* Sidebar */}
+        {(data.contributors?.length || gikaiLinks) && (
+          <div className="lg:w-[260px] shrink-0 space-y-4">
+            {gikaiLinks && <OpenGikaiLinks mapping={gikaiLinks} />}
+            {data.contributors && data.contributors.length > 0 && (
             <div className="border border-[var(--border)] rounded-lg overflow-hidden">
               <div className="px-4 py-3 bg-[var(--muted)] border-b border-[var(--border)] text-[14px] font-medium">
                 Contributors
@@ -189,6 +193,7 @@ export default async function LawPage({
                 </p>
               </div>
             </div>
+            )}
           </div>
         )}
       </div>

frontend/components/opengikai-link.tsx

@@ -0,0 +1,47 @@
+import { Icon } from "./icon";
+import { OpenGikaiMapping } from "@/lib/data";
+
+export function OpenGikaiLinks({
+  mapping,
+}: {
+  mapping: OpenGikaiMapping;
+}) {
+  if (!mapping.threads.length) return null;
+
+  return (
+    <div className="border border-[var(--border)] rounded-lg overflow-hidden">
+      <div className="px-4 py-3 bg-[var(--muted)] border-b border-[var(--border)] flex items-center gap-2 text-[14px] font-medium">
+        <Icon name="gavel" size={16} className="opacity-40" />
+        国会での審議（OpenGIKAI）
+      </div>
+      <div className="px-4 py-3 space-y-2">
+        {mapping.threads.map((thread) => (
+          <a
+            key={thread.thread_id}
+            href={thread.url}
+            target="_blank"
+            rel="noopener noreferrer"
+            className="flex items-start gap-3 rounded-lg p-2 -mx-2 hover:bg-[var(--muted)] transition-colors"
+          >
+            <div className="min-w-0 flex-1">
+              <div className="text-[14px] font-medium text-[var(--diff-hunk-text)]">
+                {thread.title}
+                <Icon
+                  name="open_in_new"
+                  size={12}
+                  className="ml-1 opacity-50"
+                />
+              </div>
+              <div className="text-[12px] opacity-50 mt-0.5">
+                {thread.date} · {thread.committee}
+              </div>
+            </div>
+          </a>
+        ))}
+        <p className="text-[11px] opacity-30 pt-1">
+          OpenGIKAIで審議の詳細を確認できます
+        </p>
+      </div>
+    </div>
+  );
+}

frontend/lib/data.ts

@@ -8,7 +8,12 @@ const TIMELINE_DIR = path.join(DATA_DIR, "timelines");
 export function getDiffIds(): string[] {
   const files = fs.readdirSync(DATA_DIR);
   return files
-    .filter((f) => f.endsWith(".json") && !f.includes("index"))
+    .filter(
+      (f) =>
+        f.endsWith(".json") &&
+        !f.includes("index") &&
+        !f.includes("mapping")
+    )
     .map((f) => f.replace(".json", ""));
 }
 
@@ -31,3 +36,26 @@ export function getTimelineData(lawId: string): LawTimeline {
   const raw = fs.readFileSync(filePath, "utf-8");
   return JSON.parse(raw) as LawTimeline;
 }
+
+export interface OpenGikaiThread {
+  thread_id: string;
+  title: string;
+  url: string;
+  date: string;
+  committee: string;
+}
+
+export interface OpenGikaiMapping {
+  law_title: string;
+  threads: OpenGikaiThread[];
+}
+
+export function getOpenGikaiLinks(
+  lawId: string
+): OpenGikaiMapping | null {
+  const mappingPath = path.join(DATA_DIR, "opengikai-mapping.json");
+  if (!fs.existsSync(mappingPath)) return null;
+  const raw = fs.readFileSync(mappingPath, "utf-8");
+  const mapping = JSON.parse(raw) as Record<string, OpenGikaiMapping>;
+  return mapping[lawId] || null;
+}

frontend/lib/life-themes.ts

@@ -12,6 +12,7 @@ const CIVIL_CODE = "129AC0000000089";
 const APPI = "415AC0000000057";
 const ROAD_TRAFFIC = "335AC0000000105";
 const LABOR_STANDARDS = "322AC0000000049";
+const COPYRIGHT = "345AC0000000048";
 
 export const LIFE_THEMES: LifeTheme[] = [
   {
@@ -68,6 +69,15 @@ export const LIFE_THEMES: LifeTheme[] = [
       "法定相続分、遺言の方式、遺産分割、特別寄与料など、相続に関わる法律の改正を追えます。",
     lawIds: [CIVIL_CODE],
   },
+  {
+    id: "creative",
+    label: "著作権・創作",
+    icon: "description",
+    description: "著作物の利用、引用、SNS投稿、AI学習など",
+    longDescription:
+      "著作権の保護範囲、引用のルール、デジタルコンテンツの利用、AI学習データの取り扱いなど、創作活動に関わる法律の改正を追えます。",
+    lawIds: [COPYRIGHT],
+  },
 ];
 
 export function getThemeById(id: string): LifeTheme | undefined {