Update KernelDB to latest in nexus and accordo

[mawad-amd]

Update KernelDB (https://github.com/AMDResearch/kerneldb) to the latest revision in all tools that depend on it:

• nexus: update the KernelDB dependency in nexus/csrc/src/CMakeLists.txt (GIT_REPOSITORY / tag or commit).
• accordo: update the KernelDB pin in accordo/pyproject.toml (and refresh uv.lock / root lockfile as needed).

Goal: test the latest KernelDB changes across the IntelliKit stack.