docs: rewrite Part 2 built-in objects — deeper, source-accurate, fully illustrated

Rewrite the object / integer / list / dict / set chapters to be more
深入浅出 for Python engineers new to CPython internals: open each concept
from familiar Python behaviour, then dive into the C, verifying every
source claim against the local CPython v3.7.0 checkout.

- add a per-operation SVG diagram for list (append/insert/resize/remove),
  dict (create/insert/lookup, combined-vs-split) and set (remove/resize)
- Chinese-ize the List/Dict/Set chapter titles and unify the section
  heading style to「<对象>的<操作>」
- fix factual issues: PyNumberMethods field order; _PyObject_HEAD_EXTRA
  is the Py_TRACE_REFS debug refchain (not the cyclic GC); the set probe
  example key; and replace fabricated big-int output with real values
- relabel the object-category diagram in Chinese; fix the set insert
  diagram; correct the two swapped stub chapter titles

Author: Prodesire

.vitepress/config.mts

@@ -50,9 +50,9 @@ export default defineConfig({
           { text: 'Python 对象初探', link: '/objects/object/' },
           { text: 'Python 整数对象', link: '/objects/long-object/' },
           { text: 'Python 字符串对象', link: '/objects/str-object/' },
-          { text: 'Python List 对象', link: '/objects/list-object/' },
-          { text: 'Python Dict 对象', link: '/objects/dict-object/' },
-          { text: 'Python Set 对象', link: '/objects/set-object/' },
+          { text: 'Python 列表对象', link: '/objects/list-object/' },
+          { text: 'Python 字典对象', link: '/objects/dict-object/' },
+          { text: 'Python 集合对象', link: '/objects/set-object/' },
           { text: '实现简版 Python', link: '/objects/simple-interpreter/' }
         ]
       },

index.md

@@ -18,10 +18,10 @@
 - [ ] Python 内建对象
     - [x] Python 对象初探
     - [x] Python 整数对象
-    - [ ] Python 字符串 对象
-    - [x] Python List 对象
-    - [x] Python Dict 对象
-    - [x] Python Set 对象
+    - [ ] Python 字符串对象
+    - [x] Python 列表对象
+    - [x] Python 字典对象
+    - [x] Python 集合对象
     - [ ] 实现简版 Python
 - [ ] Python 虚拟机
     - [ ] Python 编译结果