fix: avoid mutating payloads in emails, broadcasts, and templates

[Shubhdeep12]

• used cloned bodies / local html variables instead of writing payload.html when react is provided.
• added a test

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Summary by cubic

Stop mutating request payloads in emails, broadcasts, and templates when rendering React to HTML. This prevents side effects and keeps input objects unchanged.

• Bug Fixes
  • Use local html variables/body copies instead of writing to payload.html in emails.create, broadcasts.create/update, and templates.create.
  • Added tests to verify payload immutability for emails, broadcasts, and templates. No API changes.

^{Written for commit c6dcfb4. Summary will update on new commits.}

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/resend@862

commit: 1f7f772

[cubic-dev-ai]

No issues found across 4 files

Confidence score: 5/5

• Automated review surfaced no issues in the provided summaries.
• No files require special attention.

[gabrielmfern]

Thank you!