Added init container to dynamically extract Kubernetes conformance tests
from the OTE k8s-tests-ext binary to support OCP 4.20+ where the
kubernetes/conformance suite was removed from openshift-tests.

Changes:
- Added extract-k8s-conformance-tests init container
- Extracts k8s-tests-ext.gz from hyperkube image
- Filters conformance tests using jq or grep as fallback
- Saves test list to /tmp/shared/k8s-conformance-tests.list
- Tests container uses extracted list via entrypoint-tests.sh
- Gracefully falls back to default suite if extraction fails

This ensures the kubernetes/conformance suite continues to work on
OCP 4.20+ clusters while maintaining backward compatibility with
earlier versions.

Related: redhat-openshift-ecosystem/provider-certification-plugins#82

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Added init container to dynamically extract Kubernetes conformance tests
from the OTE k8s-tests-ext binary to support OCP 4.20+ where the
kubernetes/conformance suite was removed from openshift-tests.

Changes:
- Added extract-k8s-conformance-tests init container
- Extracts k8s-tests-ext.gz from hyperkube image
- Filters conformance tests using jq or grep as fallback
- Saves test list to /tmp/shared/k8s-conformance-tests.list
- Tests container uses extracted list via entrypoint-tests.sh
- Gracefully falls back to default suite if extraction fails

This ensures the kubernetes/conformance suite continues to work on
OCP 4.20+ clusters while maintaining backward compatibility with
earlier versions.

Related: redhat-openshift-ecosystem/provider-certification-plugins#82

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Added init container to dynamically extract Kubernetes conformance tests
from the OTE k8s-tests-ext binary to support OCP 4.20+ where the
kubernetes/conformance suite was removed from openshift-tests.

Changes:
- Added extract-k8s-conformance-tests init container
- Extracts k8s-tests-ext.gz from hyperkube image
- Filters conformance tests using jq or grep as fallback
- Saves test list to /tmp/shared/k8s-conformance-tests.list
- Tests container uses extracted list via entrypoint-tests.sh
- Gracefully falls back to default suite if extraction fails

This ensures the kubernetes/conformance suite continues to work on
OCP 4.20+ clusters while maintaining backward compatibility with
earlier versions.

Related: redhat-openshift-ecosystem/provider-certification-plugins#82

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

## Summary

This PR addresses OCP 4.20+ compatibility issues where the
`kubernetes/conformance` suite was removed from openshift-tests,
requiring dynamic extraction from the k8s-tests-ext binary.
Additionally, it refactors the client architecture to improve code
organization and maintainability.

## Problem

Starting with OCP 4.20, the `kubernetes/conformance` suite is no longer
available in openshift-tests. This causes the kube-conformance plugin to
fail when trying to run conformance tests. Additionally, the client
initialization code was scattered across multiple packages, making it
harder to maintain and test.

## Solution

### 1. Dynamic Test Extraction (OCP 4.20+ Support)

Added an init container (`extract-k8s-conformance-tests`) to the
kube-conformance plugin that:
1. Retrieves the hyperkube image from the cluster release
2. Extracts the k8s-tests-ext.gz binary
3. Runs the binary to list all tests and filters conformance tests
4. Saves the test list to `/tmp/shared/k8s-conformance-tests.list`
5. The tests container uses this list via the entrypoint script

### 2. Suite Name Enforcement by Cluster Version

Added logic to automatically detect cluster version and set the
appropriate suite name:
- **OCP 4.19 and earlier**: Uses `kubernetes/conformance` (default)
- **OCP 4.20+**: Uses `kubernetes/conformance/parallel` (new parallel
suite)

Implementation:
- Added `setSuiteName()` function in `pkg/run/run.go` that:
  - Detects cluster version using the ClusterVersion API
  - Parses version to determine if >= 4.20
  - Sets `suiteNameKubernetesConformance` ConfigMap key accordingly
- Plugin consumes this via `DEFAULT_SUITE_NAME` environment variable

### 3. Client Architecture Refactoring

Consolidated client creation into a unified `Client` struct:

**Before**:
```go
kclient, sclient, err := client.CreateClients()
restConfig, err := client.CreateRestConfig()
```

**After**:
```go
cli, err := client.NewClient()
// Access via cli.KClient, cli.SClient, cli.RestConfig
```

**Benefits**:
- Single source of truth for client initialization
- Easier to pass clients between functions
- Better testability with comprehensive unit tests
- Reduced code duplication

**Files Updated**:
- `pkg/client/client.go` - New unified Client struct
- `pkg/client/client_test.go` - Comprehensive unit tests (24 test
scenarios)
- `pkg/run/run.go` - Updated to use new client architecture
- `pkg/run/validations.go` - Updated function signatures
- `pkg/status/status.go` - Updated to use new client
- `pkg/destroy/destroy.go` - Updated to use new client
- `pkg/cmd/adm/e2ed/taintNode.go` - Updated to use new client

## Changes

### Core Implementation Files

**`data/templates/plugins/openshift-kube-conformance.yaml`**
- Added `extract-k8s-conformance-tests` init container (73 insertions)
- Extracts tests using `jq` with grep fallback for compatibility
- Gracefully handles failures by falling back to default suite
- Consumes `DEFAULT_SUITE_NAME` from ConfigMap for version-specific
suite selection
- Fixed yamllint issues (line length, string continuation)

**`pkg/run/run.go`**
- Added `setSuiteName()` function to detect cluster version and set
suite name
- Updated to use new unified `Client` struct
- Enhanced dry-run mode to print ConfigMaps as JSON
- Fixed nil pointer dereference by correcting variable shadowing
- Added suite name to plugin configuration via ConfigMap

**`pkg/client/client.go`**
- Refactored to use unified `Client` struct with KClient, SClient, and
RestConfig
- Replaced `CreateClients()` with `NewClient()` for better encapsulation
- Made `createRestConfig()` private for better encapsulation

**`pkg/client/client_test.go`** (NEW)
- Added comprehensive unit tests for client creation
- 24 test scenarios covering success and error paths
- Tests for environment variable priority and configuration fallback

### Supporting Files

**`pkg/run/validations.go`**
- Updated function signatures to accept RestConfig as parameter
- Removed dependency on client package for config creation

**`pkg/status/status.go`**
- Updated to use new Client struct
- Fixed missing assignment bug in client initialization

**`pkg/destroy/destroy.go`**
- Updated to use `NewClient()` instead of `CreateClients()`

**`pkg/cmd/adm/e2ed/taintNode.go`**
- Updated to use new client architecture

**`.containerignore` / `.gitignore`**
- Added patterns for better build artifact management

## Backward Compatibility

- ✅ **OCP 4.19 and earlier**: Falls back to `kubernetes/conformance`
suite
- ✅ **OCP 4.20+**: Uses `kubernetes/conformance/parallel` suite
dynamically
- ✅ **Graceful degradation**: If version detection or test extraction
fails, uses default suite
- ✅ **Client refactoring**: Fully backward compatible, no API changes to
external consumers

## Related PRs

- Plugins PR:
redhat-openshift-ecosystem/provider-certification-plugins#82
  - Adds entrypoint script support to consume extracted test list
- Adds `getSuiteName()` function to support `DEFAULT_SUITE_NAME`
environment variable
  - Adds failure propagation to stop dependent plugins on failure

## Testing

### Validation Performed
- ✅ All tests pass: `make test` (30 packages)
- ✅ Go vet clean: `make vet`
- ✅ YAML linting passes: `yamllint`
- ✅ Build successful: `make build`
- ✅ Client unit tests: 24 test scenarios covering all code paths
- ✅ Dry-run mode tested with verbose output

### CI Validation
- Validated with CI rehearsal job on OCP 4.21 cluster
- All linter checks passing (go_lint, yaml)

## Migration Notes

For developers updating code that uses the client package:

**Before**:
```go
kclient, sclient, err := client.CreateClients()
if err != nil {
    return err
}
```

**After**:
```go
cli, err := client.NewClient()
if err != nil {
    return err
}
// Use cli.KClient, cli.SClient, cli.RestConfig
```

---

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

---------

Co-authored-by: Claude <noreply@anthropic.com>