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[ithewei]

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[Copilot]

Pull request overview

This PR applies a set of hardening fixes across the HTTP server stack, primarily improving correctness for CORS responses, proxy error handling/timeouts, static file range handling, and multipart form file saving.

Changes:

• Add Vary: Origin behavior to CORS responses when reflecting a non-wildcard Origin.
• Harden static file Range handling (return 416 for invalid ranges) and fix proxy timeout application to the upstream connection.
• Add error handling for short writes when saving multipart form uploads to disk.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
http/server/HttpMiddleware.cpp	Updates CORS middleware to cache the Origin header value and add Vary: Origin when reflecting Origin.
http/server/HttpHandler.cpp	Adds invalid Range handling (416), switches forbidden proxy paths to immediate status responses, and applies proxy timeouts to upstream_io.
http/HttpMessage.h	Checks for short writes when persisting multipart form file content and returns 500 on failure.

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