fix: add code signing requirements to xpc connections

[ethanndickson]

Continues to address #201.

I've manually tested that this change prevents binaries not signed by the Coder Apple development team from connecting to the Helper over XPC.

Most of the PR diff is me moving the validator out of Download.swift and into Validate.swift

[ethanndickson]

• fix: add code signing requirements to xpc connections #206 : 2 dependent PRs (#209 , #210 ) 👈 (View in Graphite)
• chore: run coder connect networking from launchdaemon #203
• chore: make helper launchdaemon approval mandatory #205
• main

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[Copilot]

Pull Request Overview

This PR enhances security by adding code signing requirements to XPC connections to prevent unauthorized binaries from connecting to the Helper service. The changes implement validation that ensures only binaries signed by the Coder Apple development team can establish XPC connections.

Key changes:

• Refactored validation logic from Download.swift into a dedicated Validate.swift file
• Added xpcPeerRequirement property to enforce code signing requirements on XPC connections
• Applied code signing validation to all XPC connection points in the application

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
Coder-Desktop/VPNLib/Validate.swift	New file containing extracted validation logic with added XPC peer requirement string
Coder-Desktop/VPNLib/Download.swift	Removed validation code that was moved to Validate.swift
Coder-Desktop/VPN/NEHelperXPCClient.swift	Added code signing requirement to XPC client connection
Coder-Desktop/Coder-DesktopHelper/HelperXPCListeners.swift	Added code signing requirements to both XPC server listeners
Coder-Desktop/Coder-Desktop/AppHelperXPCClient.swift	Added code signing requirement to app helper XPC client

[Copilot]

The error type should be a name-specific validation error, not invalidIdentifier. This validation is checking the bundle name, not the identifier, so it should throw a different error type or the existing invalidIdentifier case should be renamed to be more generic.

Suggested change

	throw .invalidIdentifier(identifier: infoPlist[infoNameKey] as? String)
	throw .invalidName(name: infoPlist[infoNameKey] as? String)

[ethanndickson]

Merge activity

• Aug 6, 3:39 AM UTC: A user started a stack merge that includes this pull request via Graphite.
• Aug 6, 3:45 AM UTC: Graphite rebased this pull request as part of a merge.
• Aug 6, 3:47 AM UTC: @ethanndickson merged this pull request with Graphite.