dev: add js-parse-and-output experiment

experiments/js-parse-and-output/README.md

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+# Parsing Javascript and Generating it Back
+
+## What Purpose?
+
+This would be really useful for refactoring tools. I also want
+automatic comments to be placed when certain features are used,
+such as the [Sequence](../../src/backend/src/codex/Sequence.js)
+class, since its usefulness won't be immediately apparent where
+it appears in the source code.
+
+I turns out the state of affairs with respect to generating a
+CST for javascript... [kind of sucks](https://github.com/benjamn/recast/issues/1412).
+I hope that further discussion on the issue I linked renders the
+previous statement ironic.
+
+## So, What Next?
+
+The options I see are:
+1. Add support to recast to make use of @babel/parser tokens when
+  the `tokens: true` option is set.
+2. Add a format-preserving outputter to @babel/outputter.
+  [this is being worked on](https://github.com/babel/rfcs/pull/15)
+3. Wait for someone else to do either of the previous two things.
+4. Write a CST parser for javascript.
+
+I'm going to start with option #3. It's very disappointing that
+I don't have time to do #4, because I don't very much like solutions
+#1 and #2; I like my CSTs to be more cohesive - a pyramid of meaning -
+rather than lexer output dumped at the end of an AST.

experiments/js-parse-and-output/package.json

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+{
+  "name": "js-parse-and-output",
+  "version": "1.0.0",
+  "description": "",
+  "main": "test.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "keywords": [],
+  "author": "",
+  "license": "AGPL-3.0-only",
+  "dependencies": {
+    "@babel/generator": "^7.24.7",
+    "@babel/parser": "^7.24.7",
+    "acorn": "^8.12.1",
+    "acorn-static-class-features": "^1.0.0",
+    "escodegen": "^2.1.0",
+    "recast": "^0.23.9"
+  }
+}

experiments/js-parse-and-output/test.js

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+const babelParser = require('@babel/parser');
+const generate = (require('@babel/generator')).default;
+const fs = require('fs');
+
+const recast = require('recast');
+
+const example = fs.readFileSync('./src/backend/src/filesystem/ll_operations/ll_read.js');
+
+{
+    const ast = recast.parse(example, {
+        parser: {
+            parse (source) {
+                return babelParser.parse(source, {
+                    ranges: true,
+                    tokens: true,
+                });
+            },
+        },
+    });
+    const { code } = recast.print(ast);
+}
+
+{
+    const ast = babelParser.parse('' + example, {
+        tokens: true,
+    });
+
+    console.log(JSON.stringify(ast, undefined, '  '));
+}
+
+/*
+const { code } = generate(ast, {
+    retainLines: true,
+});
+*/
+
+// console.log(code);