durable objects: add WS batching and throughput guidance

[elithrar]

• Adds guidance on WebSocket message batching to reduce context switch overhead
• Documents DO throughput limits (~500-1,000 req/sec) and sharding strategies
• Adds TypeScriptExample for batch message handling pattern

Adds more guidance around WS batching and sharding strategies.

[github-actions]

Preview URL: https://80dd154d.preview.developers.cloudflare.com
Preview Branch URL: https://recip-do-ws.preview.developers.cloudflare.com

Files with changes (up to 15)

Original Link	Updated Link
https://developers.cloudflare.com/durable-objects/best-practices/rules-of-durable-objects/	https://recip-do-ws.preview.developers.cloudflare.com/durable-objects/best-practices/rules-of-durable-objects/
https://developers.cloudflare.com/durable-objects/best-practices/websockets/	https://recip-do-ws.preview.developers.cloudflare.com/durable-objects/best-practices/websockets/
https://developers.cloudflare.com/durable-objects/api/base/	https://recip-do-ws.preview.developers.cloudflare.com/durable-objects/api/base/

[github-actions]

This pull request requires reviews from CODEOWNERS as it changes files that match the following patterns:

Pattern	Owners
/src/content/docs/durable-objects/	@elithrar, @vy-ton, @joshthoward, @oxyjun, @lambrospetrou, @mikenomitch, @cloudflare/pcx-technical-writing