feat(symbols): Pass project platform to builtin symbol sources API (frontend)

[vaind]

Summary

Frontend changes to support platform-restricted builtin symbol sources.

This PR updates the Debug Files settings page to pass the project's platform to the builtin symbol sources API endpoint, enabling platform-based filtering of available symbol sources.

Changes

Frontend

• projectDebugFiles/index.tsx: Pass project.platform query parameter to the builtin symbol sources API

Context

This is the frontend companion to backend PR #102013 that adds:

• Platform restrictions for builtin symbol sources (e.g., Nintendo Switch private servers)
• Organization-level access control via enabledConsolePlatforms
• Automatic default symbol sources for game engines (Unity, Unreal, Godot)

Implementation

The change is minimal - it adds the platform query parameter when fetching builtin symbol sources:

platform: project.platform || undefined,

This allows the backend to filter symbol sources based on:

1. Platform match (if source has platforms restriction)
2. Organization access (for platform-restricted sources)

Deployment

Can be merged independently - This change is backward compatible:

• If backend doesn't have filtering yet: Parameter is ignored, no issues
• If backend has filtering: Platform-based filtering works immediately