Add health probe overrides to sidecar (#278)

Add support for overriding the health probes.
This is useful, for example, when injecting NetBird as a sidecar. In
that setup, the main container could start before NetBird has
established the VPN connection, resulting in failing to connect to
peers.

Example usage:
```yaml
apiVersion: netbird.io/v1alpha1
kind: SidecarProfile
metadata:
  name: netbird-sidecar
  labels:
spec:
  injectionMode: Sidecar
  setupKeyRef:
    name: netbird-setup-key
  containerOverride:
    startupProbe:
      exec:
        command: ["netbird", "status", "--check", "startup"]
      initialDelaySeconds: 10
      failureThreshold: 10
      periodSeconds: 5
```

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

* **New Features**
* SidecarProfile now supports overriding container health check probes
(startup, liveness, and readiness) for sidecar containers, enabling
fine-grained control over probe configurations.

* **Documentation**
* Updated API reference documentation with new probe override
configuration options.

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pkg/applyconfigurations/api/v1alpha1/containeroverride.go

@@ -15,6 +15,12 @@ type ContainerOverrideApplyConfiguration struct {
 	Image           *string             `json:"image,omitempty"`
 	Env             []v1.EnvVar         `json:"env,omitempty"`
 	SecurityContext *v1.SecurityContext `json:"securityContext,omitempty"`
+	// StartupProbe overrides the startup probe for the sidecar container.
+	StartupProbe *v1.Probe `json:"startupProbe,omitempty"`
+	// LivenessProbe overrides the liveness probe for the sidecar container.
+	LivenessProbe *v1.Probe `json:"livenessProbe,omitempty"`
+	// ReadinessProbe overrides the readiness probe for the sidecar container.
+	ReadinessProbe *v1.Probe `json:"readinessProbe,omitempty"`
 }
 
 // ContainerOverrideApplyConfiguration constructs a declarative configuration of the ContainerOverride type for use with
@@ -48,3 +54,27 @@ func (b *ContainerOverrideApplyConfiguration) WithSecurityContext(value v1.Secur
 	b.SecurityContext = &value
 	return b
 }
+
+// WithStartupProbe sets the StartupProbe field in the declarative configuration to the given value
+// and returns the receiver, so that objects can be built by chaining "With" function invocations.
+// If called multiple times, the StartupProbe field is set to the value of the last call.
+func (b *ContainerOverrideApplyConfiguration) WithStartupProbe(value v1.Probe) *ContainerOverrideApplyConfiguration {
+	b.StartupProbe = &value
+	return b
+}
+
+// WithLivenessProbe sets the LivenessProbe field in the declarative configuration to the given value
+// and returns the receiver, so that objects can be built by chaining "With" function invocations.
+// If called multiple times, the LivenessProbe field is set to the value of the last call.
+func (b *ContainerOverrideApplyConfiguration) WithLivenessProbe(value v1.Probe) *ContainerOverrideApplyConfiguration {
+	b.LivenessProbe = &value
+	return b
+}
+
+// WithReadinessProbe sets the ReadinessProbe field in the declarative configuration to the given value
+// and returns the receiver, so that objects can be built by chaining "With" function invocations.
+// If called multiple times, the ReadinessProbe field is set to the value of the last call.
+func (b *ContainerOverrideApplyConfiguration) WithReadinessProbe(value v1.Probe) *ContainerOverrideApplyConfiguration {
+	b.ReadinessProbe = &value
+	return b
+}