更新前端静态网页获取方式，放弃使用后端获取api

frontend/node_modules/xmlchars/README.md

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+Utilities for determining whether characters belong to character classes defined
+by the XML specs.
+
+## Organization
+
+It used to be that the library was contained in a single file and you could just
+import/require/what-have-you the `xmlchars` module. However, that setup did not
+work well for people who cared about code optimization. Importing `xmlchars`
+meant importing *all* of the library and because of the way the code was
+generated there was no way to shake the resulting code tree.
+
+Different modules cover different standards. At the time this documentation was
+last updated, we had:
+
+* `xmlchars/xml/1.0/ed5` which covers XML 1.0 edition 5.
+* `xmlchars/xml/1.0/ed4` which covers XML 1.0 edition 4.
+* `xmlchars/xml/1.1/ed2` which covers XML 1.0 edition 2.
+* `xmlchars/xmlns/1.0/ed3` which covers XML Namespaces 1.0 edition 3.
+
+## Features
+
+The "things" each module contains can be categorized as follows:
+
+1. "Fragments": these are parts and pieces of regular expressions that
+correspond to the productions defined in the standard that the module
+covers. You'd use these to *build regular expressions*.
+
+2. Regular expressions that correspond to the productions defined in the
+standard that the module covers.
+
+3. Lists: these are arrays of characters that correspond to the productions.
+
+4. Functions that test code points to verify whether they fit a production.