feat: Add Lambda-Runtime-Invocation-Id support for cross-wiring protection

[vip-amzn]

Summary

Add Lambda-Runtime-Invocation-Id header support for cross-wiring protection.

The RIC now echoes the invocation ID received from RAPID on /next back on /response and /error, enabling RAPID to detect and reject stale responses from timed-out invocations.

Problem

On Lambda Managed Instances (LMI) and On-Demand (OD), when an invoke times out, the runtime process continues running in the background. If a new invoke arrives with the same requestId, RAPID accepts it. The still-running old invocation eventually posts its response, and RAPID matches it to the new invoke — delivering the wrong response (cross-wiring).

Solution

RAPID sends a unique per-invoke nonce via Lambda-Runtime-Invocation-Id header on /next. The runtime echoes it back on /response and /error. RAPID validates the match before accepting the response.

Changes

• runtime_client.cpp: Parse Lambda-Runtime-Invocation-Id from /next response, pass to post_success/post_failure via z format (accepts None → nullptr)
• lambda_runtime_client.py: Thread invocation_id through to native client
• bootstrap.py: Pass invocation_id from event request to response/error posting
• deps/: Patch aws-lambda-cpp to support invocation_id in get_next/do_post
• Unit tests: 6 new invocation-id specific tests + fix existing assertions for the new parameter

Backward Compatibility

Fully backward compatible in both directions:

• If RAPID doesn't send the header → RIC doesn't see it → doesn't echo → no behavior change
• If RIC doesn't echo it (old version) → RAPID skips validation → no behavior change

Testing

• 95 unit tests pass (includes 6 new invocation-id tests)
• E2E tested with updated RIE binary (validates invocation-id echo) and stock RIE (backward compat verified)