feat: add platform-specific implementations for quote verification

- Introduced conditional compilation for Intel SGX/TDX quote verification based on target OS and architecture.
- Moved Intel-specific logic to a separate module and added a fallback for unsupported platforms.

This is done, so we can pull in the `teepot` crate even on `linux-x86_64`
without the Intel SGX SDK lib dependency.

Signed-off-by: Harald Hoyer <harald@matterlabs.dev>

crates/teepot-tee-quote-verification-rs/src/empty.rs

@@ -0,0 +1,4 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright (c) 2025 Matter Labs
+
+pub const NOTHING_TO_SEE_HERE: u8 = 0;