Remove x64 builds from GitHub Actions workflows

[Copilot]

Removes x64 (64-bit) platform builds from CI/CD workflows, retaining only Win32 (32-bit) debug and release configurations.

Changes

• build-emule.yml: Removed x64 from build matrix in build and build-debug jobs
• release.yml: Removed x64 from build matrix in build-release job and deleted x64 artifact download step in create-installer job

# Before
strategy:
  matrix:
    platform: [Win32, x64]

# After  
strategy:
  matrix:
    platform: [Win32]

Reduces CI resource usage by ~50% (1 platform vs 2).

Original prompt

Remove x64 build in github actions, only windows 32 debug and release

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