feat(cni-installer): integrate cni installer (#784)

Build cni installer into the runtime docker image.

Drop tooling from the runtime docker image required to enable the installer shell script. Remove the shell script and jq filter file from the repo.

Tested by running through the plugin integration tests locally.
Signed-off by: Raymond Kroeker raymond@buoyant.io

Author: raykroeker

Dockerfile-cni-plugin

@@ -4,13 +4,18 @@
 FROM --platform=$BUILDPLATFORM golang:1.26.4-alpine as go
 WORKDIR /build
 COPY --link go.mod go.sum ./
+COPY --link ./cni-install ./cni-install
 COPY --link ./cni-plugin ./cni-plugin
+COPY --link ./internal ./internal
 COPY --link ./proxy-init ./proxy-init
 COPY --link ./pkg ./pkg
 RUN go mod download
 ARG TARGETARCH
 RUN CGO_ENABLED=0 GOOS=linux GOARCH=$TARGETARCH GO111MODULE=on \
     go build -o /go/bin/linkerd-cni -mod=readonly -ldflags "-s -w" -v ./cni-plugin/
+RUN CGO_ENABLED=0 GOOS=linux GOARCH=$TARGETARCH GO111MODULE=on \
+    go build -o /go/bin/linkerd2-cni-install -mod=readonly -ldflags "-s -w" -v ./cni-install/
+
 
 FROM --platform=$BUILDPLATFORM ghcr.io/linkerd/dev:v50-rust-musl as cni-repair-controller
 WORKDIR /build
@@ -41,18 +46,8 @@ RUN --mount=type=cache,target=target \
 
 FROM --platform=$TARGETPLATFORM alpine:3.24.1 as runtime
 WORKDIR /linkerd
-RUN apk add \
-    # For inotifywait
-    inotify-tools \
-    # For pgrep
-    procps \
-    bash \
-    jq
-
 COPY --from=go /go/bin/linkerd-cni /opt/cni/bin/
+COPY --from=go /go/bin/linkerd2-cni-install /usr/bin/
 COPY --from=cni-repair-controller /build/linkerd-cni-repair-controller /usr/lib/linkerd/
 COPY LICENSE .
-COPY cni-plugin/deployment/scripts/install-cni.sh .
-COPY cni-plugin/deployment/scripts/filter.jq .
-ENV PATH=/linkerd:/opt/cni/bin:$PATH
-CMD ["install-cni.sh"]
+CMD ["/usr/bin/linkerd2-cni-install"]