docs: add Japanese translate documents (#1812)

* docs: add Japanese documents (`ja/docs`)

* docs: add Japanese documents (`ja/codes`)

* docs: add Japanese documents

* Remove pythontutor blocks in ja/

* Add an empty at the end of each markdown file.

* Add the missing figures (use the English version temporarily).

* Add index.md for Japanese version.

* Add index.html for Japanese version.

* Add missing index.assets

* Fix backtracking_algorithm.md for Japanese version.

* Add avatar_eltociear.jpg. Fix image links on the Japanese landing page.

* Add the Japanese banner.

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Co-authored-by: krahets <krahets@163.com>

ja/codes/python/chapter_greedy/max_capacity.py

@@ -0,0 +1,33 @@
+"""
+File: max_capacity.py
+Created Time: 2023-07-21
+Author: krahets (krahets@163.com)
+"""
+
+
+def max_capacity(ht: list[int]) -> int:
+    """最大容量：貪欲法"""
+    # i、j を初期化、配列の両端で分割させる
+    i, j = 0, len(ht) - 1
+    # 初期最大容量は 0
+    res = 0
+    # 2 つの板が出会うまで貪欲選択をループ
+    while i < j:
+        # 最大容量を更新
+        cap = min(ht[i], ht[j]) * (j - i)
+        res = max(res, cap)
+        # 短い板を内側に移動
+        if ht[i] < ht[j]:
+            i += 1
+        else:
+            j -= 1
+    return res
+
+
+"""ドライバーコード"""
+if __name__ == "__main__":
+    ht = [3, 8, 5, 2, 7, 7, 3, 4]
+
+    # 貪欲アルゴリズム
+    res = max_capacity(ht)
+    print(f"最大容量は {res}")