feat(defer): add options parameter with name field for debugging

[uhyo]

Add a DeferOptions interface as the second parameter to the defer function.
The optional name field helps with debugging RSC payloads:

• Development: name is included in the payload file name
• Production: name is logged when the payload file is emitted

[Copilot]

Pull request overview

This PR adds an optional DeferOptions parameter to the defer() function, introducing a name field for debugging purposes. The name is included in development payload file names (via sanitized ID) and logged during production builds when files are emitted.

Changes:

• Added DeferOptions interface with optional name field for debugging
• Added sanitizeName() function to sanitize names for use in file paths
• Updated defer() function to accept options parameter and incorporate name into payload IDs
• Threaded the name field through the entire processing pipeline from registration through build output

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
packages/static/src/rsc/defer.tsx	Added DeferOptions interface, sanitizeName function, and updated defer() to accept options; modified DeferEntry and DeferRegistry to store and propagate name field
packages/static/src/entries/server.ts	Exported DeferOptions type for public API consumption
packages/static/src/build/rscProcessor.ts	Updated ProcessedComponent and RawComponent interfaces to include name field; modified processRscComponents to track and propagate names
packages/static/src/build/buildApp.ts	Updated writeFileNormal to accept and log optional name parameter when writing deferred component files

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[Copilot]

The sanitizeName function can return an empty string when the input contains only non-alphanumeric characters (e.g., "!!!" or "###"). This would result in a rawId starting with a hyphen like "-abc-123-uuid", which may cause issues with file paths or module IDs. Consider adding a check to handle this edge case, such as falling back to undefined when the sanitized result is empty.