feat: add i18n support, avaiable languages are 'en' and 'ja'

package.json

@@ -37,13 +37,17 @@
     "test:watch": "vitest",
     "e2e": "./scripts/e2e/exec_e2e.sh",
     "e2e:start-server": "./scripts/e2e/start_server.sh",
-    "e2e:capture-snapshots": "./scripts/e2e/capture_snapshots.sh"
+    "e2e:capture-snapshots": "./scripts/e2e/capture_snapshots.sh",
+    "lingui:extract": "lingui extract --clean",
+    "lingui:compile": "lingui compile --typescript"
   },
   "dependencies": {
     "@anthropic-ai/claude-code": "^2.0.22",
     "@effect/platform": "^0.92.1",
     "@effect/platform-node": "^0.98.4",
     "@hono/zod-validator": "^0.7.4",
+    "@lingui/core": "^5.5.1",
+    "@lingui/react": "^5.5.1",
     "@radix-ui/react-avatar": "^1.1.10",
     "@radix-ui/react-checkbox": "^1.3.3",
     "@radix-ui/react-collapsible": "^1.1.12",
@@ -56,6 +60,7 @@
     "@tanstack/react-query": "^5.90.5",
     "class-variance-authority": "^0.7.1",
     "clsx": "^2.1.1",
+    "date-fns": "^4.1.0",
     "effect": "^3.18.4",
     "es-toolkit": "^1.40.0",
     "hono": "^4.10.1",
@@ -79,6 +84,10 @@
   },
   "devDependencies": {
     "@biomejs/biome": "^2.2.6",
+    "@lingui/cli": "^5.5.1",
+    "@lingui/conf": "^5.5.1",
+    "@lingui/format-json": "^5.5.1",
+    "@lingui/loader": "^5.5.1",
     "@tailwindcss/postcss": "^4.1.14",
     "@tsconfig/strictest": "^2.0.6",
     "@types/node": "^24.8.1",