Make more progress on package configuration, fill out C docs.

packages/js/src/document.ts

@@ -1,5 +1,5 @@
-import type { Reader } from './readers/reader'
-import { createLineData, parseLine } from './parser'
+import type { Reader } from './readers/reader.js'
+import { createLineData, parseLine } from './parser.js'
 
 // Container for a handful of convenience functions for parsing documents
 // Obtained from useDocument() below

packages/js/src/index.ts

@@ -1,2 +1,2 @@
-export * from './parser'
-export * from './document'
+export * from './parser.js'
+export * from './document.js'

packages/js/src/readers/js-string.ts

@@ -1,4 +1,4 @@
-import type { Reader } from './reader'
+import type { Reader } from './reader.js'
 
 /**
  * Get a simple `Reader` function that always returns the next line

packages/js/src/readers/node-readline.ts

@@ -1,6 +1,6 @@
-import fs from 'node:fs'
-import readline from 'node:readline/promises'
-import type { Reader } from './reader'
+import fs from 'fs'
+import readline from 'readline/promises'
+import type { Reader } from './reader.js'
 
 
 /**