perf(ext/node): improve `Buffer` from string performance (#24567)

Fixes https://github.com/denoland/deno/issues/24323

- Use a Buffer pool for `fromString`
- Implement fast call base64 writes
- Direct from string `create` method for each encoding op

```
$ deno bench -A bench.mjs # 1.45.1+fee4d3a
cpu: Apple M1 Pro
runtime: deno 1.45.1+fee4d3a (aarch64-apple-darwin)

benchmark                time (avg)             (min … max)       p75       p99      p999
----------------------------------------------------------- -----------------------------
Buffer.from base64      550 ns/iter     (490 ns … 1'265 ns)    572 ns    606 ns  1'265 ns
Buffer#write base64     285 ns/iter       (259 ns … 371 ns)    307 ns    347 ns    360 ns

$ ~/gh/deno/target/release/deno bench -A bench.mjs # this PR
cpu: Apple M1 Pro
runtime: deno dev (aarch64-apple-darwin)

benchmark                time (avg)             (min … max)       p75       p99      p999
----------------------------------------------------------- -----------------------------
Buffer.from base64      151 ns/iter       (145 ns … 770 ns)    148 ns    184 ns    648 ns
Buffer#write base64   62.58 ns/iter     (60.79 ns … 157 ns)  61.65 ns  75.79 ns    141 ns

$ node bench.mjs # v22.4.0
cpu: Apple M1 Pro
runtime: node v22.4.0 (arm64-darwin)

benchmark                time (avg)             (min … max)       p75       p99      p999
----------------------------------------------------------- -----------------------------
Buffer.from base64      163 ns/iter     (96.92 ns … 375 ns)  99.45 ns    127 ns    220 ns
Buffer#write base64   75.48 ns/iter     (74.97 ns … 134 ns)  75.17 ns  81.83 ns  96.84 ns
```

1 files changed, 17 insertions, 0 deletions

diff --git a/ext/node/polyfills/internal_binding/_utils.ts b/ext/node/polyfills/internal_binding/_utils.ts
index 74dc3cbcd..0b1e1709d 100644
--- a/ext/node/polyfills/internal_binding/_utils.ts
+++ b/ext/node/polyfills/internal_binding/_utils.ts
@@ -7,6 +7,7 @@ import {
   forgivingBase64Decode,
   forgivingBase64UrlDecode,
 } from "ext:deno_web/00_infra.js";
+import { op_base64_write } from "ext:core/ops";
 
 export function asciiToBytes(str: string) {
   const length = str.length;
@@ -27,6 +28,22 @@ export function base64ToBytes(str: string) {
   }
 }
 
+export function base64Write(
+  str: string,
+  buffer: Uint8Array,
+  offset: number = 0,
+  length?: number,
+): number {
+  length = length ?? buffer.byteLength - offset;
+  try {
+    return op_base64_write(str, buffer, offset, length);
+  } catch {
+    str = base64clean(str);
+    str = str.replaceAll("-", "+").replaceAll("_", "/");
+    return op_base64_write(str, buffer, offset, length);
+  }
+}
+
 const INVALID_BASE64_RE = /[^+/0-9A-Za-z-_]/g;
 function base64clean(str: string) {
   // Node takes equal signs as end of the Base64 encoding