fix: Only parse topology when it actually exists

This also helps avoid unnecessary logging that happens each time we need to
reconstruct ResourceSlice state and it's cloud provider attributes.

feat: Enhance metrics to tag managed_pod in nri_hooks

add DRA and NRI latency, success metrics and tests for metrics

fix: Delete singleton links if they are removed

Currently if a link is deleted as the last link the driver will never reconcile and leave it in the resource slice. Ensure that this does not happen since that could lead to bad assignments by the scheduler.

interface dhcp configuration

dhcp should be an opt-in option because running it can cause delays
on pod startup on environments that don't have dhcp enabled.

Change-Id: I2905788c261583d86a5701576c2e61a245138c02

document tpu multinic

Change-Id: I535e6deebb36a861c32ded91f33549815e7f0275

do not fail to add routes that already exist

Change-Id: I948f861a1465bbb0a9b3fee903934388b78584d5

don't adjust rdma devchar duplicates

Change-Id: I9028ba278a99f3fd015b981106777ce4cacade2d

fix readme links

Change-Id: I5652d9cf7540e17129d9ca76ec9d6bcd7bb18d31

optimize image build

- set GOARCH from TARGETARCH
- cache go modules independently of source code changes
- don't set redundant GOOS (the build env is inherently linux)