Fix capture logic for inner closures (#9754)

# Description

This fixes the variable capture logic for closures in two cases:

* Closures inside of closures did not properly register the closures (or
lack thereof) in the outer closure
* Closures which called their inner closures before definition did not
properly calculate the closures of the outer closure

Example of the first case:
```
do { let b = 3; def c [] { $b }; c }
```

Example of the second case (notice `c` is called before it is defined):
```
do { let b = 3; c; def c [] { $b }; c }
```

# User-Facing Changes
This should strictly allow closures to work more correctly.

# Tests + Formatting
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src/tests/test_parser.rs

@@ -655,3 +655,13 @@ fn def_with_in_var_mut_2() -> TestResult {
         "3",
     )
 }
+
+#[test]
+fn properly_nest_captures() -> TestResult {
+    run_test(r#"do { let b = 3; def c [] { $b }; c }"#, "3")
+}
+
+#[test]
+fn properly_nest_captures_call_first() -> TestResult {
+    run_test(r#"do { let b = 3; c; def c [] { $b }; c }"#, "3")
+}