PR #115 review: address Tyler's comments

- bring-your-own-api-key.mdx 'Platform credits' note: Tyler correctly
  pointed out that platform credits also apply for cloud agent runs.
  Rewrite the line to lead with the cloud-agent case ('apply to every
  cloud agent run on any plan') and then cover the local-runs case
  ('and to local agent runs on Business and Enterprise when using
  BYOK, a custom inference endpoint, or BYOLLM').
- bring-your-own-api-key.mdx 'How BYOK works' opening: drop the
  misleading 'directly to the model provider' phrasing since requests
  still flow through Warp's infrastructure. Now reads 'Warp uses
  these API keys when routing your agent requests to the model
  provider you've configured.'

Tyler's third comment was a stylistic preference for 'need' over
'require' on the page note, which already uses 'need' here. The
parallel 'require' phrasing in pricing-faqs.mdx will be normalized on
PR #116.

Co-Authored-By: Oz <oz-agent@warp.dev>

Author: hongyi-chen

src/content/docs/support-and-community/plans-and-billing/bring-your-own-api-key.mdx

@@ -27,13 +27,13 @@ Warp offers three ways to bring your own AI infrastructure. Use this table to pi
 
 See [warp.dev/pricing](https://www.warp.dev/pricing) for current plan availability.
 
-Platform credits may apply for local agent runs on Business and Enterprise when using BYOK, a custom inference endpoint, or BYOLLM. See [platform credits](/support-and-community/plans-and-billing/platform-credits/).
+Platform credits apply to every cloud agent run on any plan, and to local agent runs on Business and Enterprise when using BYOK, a custom inference endpoint, or BYOLLM. See [platform credits](/support-and-community/plans-and-billing/platform-credits/) for the full breakdown.
 
 ## How BYOK works
 
 When you add your own model API keys in Warp, those keys are stored **locally on your device** and are **never synced to the cloud**.
 
-Warp uses these API keys to route your agent requests directly to the model provider you've configured.
+Warp uses these API keys when routing your agent requests to the model provider you've configured.
 
 :::caution
 BYOK does not apply to [Cloud Agents](/agent-platform/cloud-agents/overview/). Because your API keys are stored locally on your device, they are not available to cloud-hosted agent runs. Cloud agent runs always consume [Warp credits](/support-and-community/plans-and-billing/credits/).