Upgrade Protobuf to v33.6 (#29906)
### Description
- **Native and vcpkg**
- Pin Protobuf source and prebuilt `protoc` archives to `v33.6`.
- Update the custom vcpkg port to `6.33.6`, including v33-compatible
patches and tool naming.
- Remove upstreamed compatibility patches; retain the Android linker
patch.
- **Packaging and CI**
- Update Python packages to `protobuf==6.33.6`.
- Update .NET packages and tooling to `Google.Protobuf` /
`Google.Protobuf.Tools` `3.33.6`.
- Align Dawn's vcpkg Protobuf constraint.
### Motivation and Context
Newer Protobuf is required for static iOS integration so dependent
libraries can share ONNX Runtime's Protobuf symbols without
duplicate-symbol linker conflicts.
<!-- START COPILOT CODING AGENT SUFFIX -->
- Fixes #29905
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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: Tianlei Wu <tlwu@microsoft.com>
