reduce file size of dockerfiles & change dockerfiles for improved caching & some cleanups (#3989)

# Summary
- we have been pushing way too much into our docker images -> proof in
[1]
- merge race operator dockerfile with normal one, if race image can be
built -> we are fine
- remove not used .dcar dockerfiles
- update agent dockerfile for better caching
- 12.0.30 removal in release.json, doesn't exist anymore

## [1] Proof of work for size of docker images
**with change**
```
docker images
REPOSITORY                                                                       TAG           IMAGE ID       CREATED         SIZE
REDACTED   1.25.0-race   e3c9ca7a8c66   4 minutes ago   35.3MB
sonar-docker-build-8055                                                          latest        e3c9ca7a8c66   4 minutes ago   35.3MB
REDACTED   1.25.0        33656a37a5e0   9 minutes ago   14.2MB
sonar-docker-build-4712
```

**prior to this change operator image**
```
REDACTED                  1.25.0-race   8477bd6e2caf   3 minutes ago   48.1MB
sonar-docker-build-6342                                                                         latest        8477bd6e2caf   3 minutes ago   48.1MB
REDACTED                  1.25.0        f150f4701452   9 minutes ago   26.9MB
sonar-docker-build-5152                                                                         latest        f150f4701452   9 minutes ago   26.9MB
```

## Proof of speed
build now takes around 10-20% less time and are smaller:
https://spruce.mongodb.com/task/ops_manager_kubernetes_init_test_run_build_operator_ubi_patch_b868d02f6fd0e42d271d33da66f5130744c8804f_676964ab99313b0007506c98_24_12_23_13_25_01/logs?execution=0

Author: nammn

.dockerignore

@@ -1,6 +1,76 @@
-vendor/**
-pkg/client/**
-samples/*
-public/*
-.git/**
-bin/**
+# Exclude version control folders and configuration
+.git/
+.gitignore
+.github/
+
+# Generated or build-related directories
+.generated/
+vendor/
+pkg/client/
+docker/mongodb-enterprise-tests
+scripts/
+samples/
+.multi_cluster_local_test_files/
+
+# Python-related ignore patterns
+__pycache__/
+*.pyc
+*.pyo
+*.pyd
+*.toml
+
+# Virtual environment and dependency files
+venv/
+.env
+
+# Ignore temporary and system files
+*.swp
+*.bak
+*.tmp
+.DS_Store
+Thumbs.db
+
+# Testing-related files
+*.test.*
+*_test.go
+cover.out
+
+# Compiled and object files
+*.o
+*.so
+*.dylib
+
+# Logs and binary artifacts
+logs/
+*.log
+*.csv
+*.tgz
+
+# Tools and binaries
+bin/
+tools.go
+
+# Kubernetes and operator-related artifacts
+deploy/
+config/manifests/
+helm_chart/templates/
+helm_chart/crds/
+public/
+
+# Documentation files
+docs/
+*.md
+
+# IDE and editor config files
+*.iml
+*.idea/
+.vscode/
+
+# Data and build artifacts
+blobs/
+ssdlc-report/
+
+# Dockerfiles or specific project directories
+# (Add Docker-specific exclusion patterns here if known)
+
+# By excluding directories, specific files inside them are also excluded, so listing every specific file isn't necessary unless needed.

docker/mongodb-agent/Dockerfile.builder

@@ -3,10 +3,21 @@
 ARG init_database_image
 FROM ${init_database_image} as init_database
 
-# Build compilable stuff
+FROM public.ecr.aws/docker/library/golang:1.23 as dependency_downloader
+
+WORKDIR /go/src/github.com/10gen/ops-manager-kubernetes/
+
+COPY go.mod go.sum ./
+
+RUN go mod download
+
 FROM public.ecr.aws/docker/library/golang:1.23 as readiness_builder
-COPY . /go/src/github.com/10gen/ops-manager-kubernetes
-WORKDIR /go/src/github.com/10gen/ops-manager-kubernetes
+
+WORKDIR /go/src/github.com/10gen/ops-manager-kubernetes/
+
+COPY --from=dependency_downloader /go/pkg /go/pkg
+COPY go.mod go.sum ./
+
 RUN CGO_ENABLED=0 go build -o /readinessprobe github.com/mongodb/mongodb-kubernetes-operator/cmd/readiness
 RUN CGO_ENABLED=0 go build -o /version-upgrade-hook github.com/mongodb/mongodb-kubernetes-operator/cmd/versionhook
 

docker/mongodb-enterprise-database/Dockerfile.dcar

@@ -42,11 +42,8 @@ RUN mkdir -p /data
 RUN cat release.json | jq -r '.supportedImages."mongodb-agent" | { "supportedImages": { "mongodb-agent": . } }' > /data/om_version_mapping.json
 RUN chmod +r /data/om_version_mapping.json
 
-RUN go install github.com/go-delve/delve/cmd/dlv@latest
-
 FROM scratch
 
-COPY --from=builder /go/bin/dlv /data/dlv
 COPY --from=builder /build/mongodb-enterprise-operator /data/
 COPY --from=builder /data/om_version_mapping.json /data/om_version_mapping.json
 

docker/mongodb-enterprise-init-database/Dockerfile.dcar

@@ -30,10 +30,6 @@ COPY --from=base /data/licenses /licenses/
 
 USER 2000
 
-{% if debug|default(false) %}
-COPY --from=base /data/dlv /usr/local/bin/dlv
-{% endif %}
-
 ENTRYPOINT exec /usr/local/bin/mongodb-enterprise-operator
 
 {% block healthcheck %}

docker/mongodb-enterprise-init-ops-manager/Dockerfile.dcar

@@ -8,4 +8,5 @@ RUN microdnf update \
     --disableplugin=subscription-manager \
     --disablerepo=* --enablerepo=ubi-9-appstream-rpms --enablerepo=ubi-9-baseos-rpms -y \
     && rm -rf /var/cache/yum
+RUN microdnf install -y glibc-langpack-en
 {% endblock -%}