feat(node): expose seek, tell, bounded read, readRanges and close on BlobFile (#4348)

Closes #4300.

The TypeScript `BlobFile` only had `size()`, `read()` and `readRange()`,
while the Rust `BlobFile` behind it also has `seek`, `tell`,
`read_up_to`, `read_ranges` and `close`. This exposes those on the Node
binding:

- `read(maxBytes?)` reads at most `maxBytes` from the cursor (Rust
`read_up_to`). Without the argument it reads to the end, as before.
- `readRanges([{ start, end }, ...])` reads several half-open ranges and
returns one buffer per range, in order. Like `readRange`, it does not
move the cursor.
- `seek(position)` and `tell()` move and report the cursor.
- `close()` releases the handle, and `isClosed()` reports it. Every
read, `seek` and `tell` after `close()` fails with "blob file is already
closed". A second `close()` does nothing. The binding keeps its own
`closed` flag, the same way the Python `BlobFile` does.

Offsets and lengths are `bigint`, like `readRange` and `size()`.
`BlobRange` is exported as a type.

The new tests in `table.test.ts` cover chunked reads with
`read(maxBytes)`, `seek` and `tell`, a negative seek position,
`readRanges` order and cursor, a `readRanges` end past the blob size,
and reads after `close()`. The Node docs under `docs/src/js` are
regenerated with `pnpm run docs`.

I left the `ReadableStream`/async iterator idea from the issue out of
this PR. The AbortSignal work in #4288 touches the same methods, so it
can follow on top of this.

docs/src/js/classes/BlobFile.md

@@ -10,16 +10,50 @@ A lazy handle to blob bytes. Create one with [Table.fetchBlobFiles](Table.md#fet
 
 ## Methods
 
+### close()
+
+```ts
+close(): Promise<void>
+```
+
+Releases the handle. Reads after `close()` fail. Calling it again does
+nothing.
+
+#### Returns
+
+`Promise`&lt;`void`&gt;
+
+***
+
+### isClosed()
+
+```ts
+isClosed(): boolean
+```
+
+Returns true after [BlobFile.close](BlobFile.md#close).
+
+#### Returns
+
+`boolean`
+
+***
+
 ### read()
 
 ```ts
-read(): Promise<Buffer>
+read(maxBytes?): Promise<Buffer>
 ```
 
-Reads from the cursor to the end and advances the cursor.
+Reads from the cursor and advances the cursor.
 
-A second call returns an empty buffer. [BlobFile.readRange](BlobFile.md#readrange) does
-not move the cursor.
+Reads to the end when `maxBytes` is omitted, or at most `maxBytes` bytes
+otherwise. Returns an empty buffer at the end of the blob.
+[BlobFile.readRange](BlobFile.md#readrange) does not move the cursor.
+
+#### Parameters
+
+* **maxBytes?**: `bigint`
 
 #### Returns
 
@@ -49,6 +83,45 @@ Fails when `end` is past the blob size. Does not move the cursor.
 
 ***
 
+### readRanges()
+
+```ts
+readRanges(ranges): Promise<Buffer[]>
+```
+
+Reads several half-open byte ranges. Returns one buffer per range, in
+the order given.
+
+Fails when any `end` is past the blob size. Does not move the cursor.
+
+#### Parameters
+
+* **ranges**: [`BlobRange`](../type-aliases/BlobRange.md)[]
+
+#### Returns
+
+`Promise`&lt;`Buffer`[]&gt;
+
+***
+
+### seek()
+
+```ts
+seek(position): Promise<void>
+```
+
+Moves the cursor to `position`, in bytes from the start of the blob.
+
+#### Parameters
+
+* **position**: `bigint`
+
+#### Returns
+
+`Promise`&lt;`void`&gt;
+
+***
+
 ### size()
 
 ```ts
@@ -60,3 +133,17 @@ Returns the blob size in bytes.
 #### Returns
 
 `bigint`
+
+***
+
+### tell()
+
+```ts
+tell(): Promise<bigint>
+```
+
+Returns the cursor position in bytes.
+
+#### Returns
+
+`Promise`&lt;`bigint`&gt;

docs/src/js/globals.md

@@ -158,6 +158,7 @@
 - [AnalyzePlanDistributedMetrics](type-aliases/AnalyzePlanDistributedMetrics.md)
 - [BaseTokenizer](type-aliases/BaseTokenizer.md)
 - [BlobOptions](type-aliases/BlobOptions.md)
+- [BlobRange](type-aliases/BlobRange.md)
 - [Data](type-aliases/Data.md)
 - [DataLike](type-aliases/DataLike.md)
 - [FieldLike](type-aliases/FieldLike.md)

docs/src/js/type-aliases/BlobRange.md

@@ -0,0 +1,27 @@
+[**@lancedb/lancedb**](../README.md) • **Docs**
+
+***
+
+[@lancedb/lancedb](../globals.md) / BlobRange
+
+# Type Alias: BlobRange
+
+```ts
+type BlobRange: object;
+```
+
+A half-open byte range `[start, end)` for [BlobFile.readRanges](../classes/BlobFile.md#readranges).
+
+## Type declaration
+
+### end
+
+```ts
+end: bigint;
+```
+
+### start
+
+```ts
+start: bigint;
+```