docs: update README and loader documentation

README.md

@@ -128,16 +128,40 @@ Parses a value string according to the given schema.
 
 Creates a validation function for the given schema.
 
+### `schemaToTypeString(schema: Schema): string`
+
+Converts a schema AST back to a human-readable type string.
+
+### `ParseError`
+
+Error class thrown for invalid schema syntax.
+
+### Types
+
+The following TypeScript types are exported:
+
+- `Schema` — union of all schema AST node types
+- `ParsedSchema` — the return type of `defineSchema()`
+- `PrimitiveSchema`, `TupleSchema`, `ArraySchema` — AST node types
+- `ReferenceSchema`, `ReverseReferenceSchema` — reference AST node types
+- `StringLiteralSchema`, `UnionSchema` — literal and union AST node types
+
 ## Schema Syntax
 
 | Type | Schema | Example Value |
 |------|--------|---------------|
 | String | `string` or `identifier` | `hello` |
-| Number | `number` | `42` |
+| Int | `int` | `42` |
+| Float | `float` | `3.14` |
+| Number | `number` | `42` or `3.14` |
 | Boolean | `boolean` | `true` or `false` |
 | Tuple | `[Type1; Type2; ...]` | `[hello; 42; true]` or `hello; 42; true` |
 | Array | `Type[]` or `[Type][]` | `[1; 2; 3]` or `1; 2; 3` |
 | Array of Tuples | `[Type1; Type2][]` | `[[a; 1]; [b; 2]]` or `[a; 1]; [b; 2]` |
+| Union | `Type1 \| Type2` | `hello` or `42` (matches first valid member) |
+| String Literal | `'on' \| 'off'` or `"red"` | `on` or `off` |
+| Reference | `@tablename` or `@tablename[]` | (resolved at CSV load time) |
+| Reverse Reference | `~tablename(fk)` | (resolved at CSV load time) |
 
 ## Notes
 
@@ -145,10 +169,7 @@ Creates a validation function for the given schema.
 - Outermost brackets `[]` are optional for tuple and array values
 - Special characters can be escaped with backslash: `\;`, `\[`, `\]`, `\\`
 - Empty arrays/tuples are not allowed
-
-## CSV Loader
-
-For loading CSV files with schema validation in rspack, see [csv-loader.md](./csv-loader.md).
+- For CSV loading with reference resolution, see [csv-loader.md](./csv-loader.md)
 
 ```javascript
 // rspack.config.js