Switch README diagrams to vertical layout

labs/ci-cd/README.md

@@ -5,7 +5,7 @@ This folder is intended for CI/CD experiments such as pipeline layouts, validati
 ## Diagram
 
 ```mermaid
-flowchart LR
+flowchart TD
   A["ci-cd"] --> B["Build"]
   A --> C["Test"]
   A --> D["Package"]

labs/docker/README.md

@@ -5,7 +5,7 @@ This folder is reserved for Docker-focused lab work. It is intended for image bu
 ## Diagram
 
 ```mermaid
-flowchart LR
+flowchart TD
   A["docker"] --> B["Dockerfiles"]
   A --> C["Compose stacks"]
   A --> D["Container debugging"]

labs/kubernetes/README.md

@@ -5,7 +5,7 @@ This folder is intended for Kubernetes lab work such as manifests, troubleshooti
 ## Diagram
 
 ```mermaid
-flowchart LR
+flowchart TD
   A["kubernetes"] --> B["Workloads"]
   A --> C["Services"]
   A --> D["Ingress and networking"]

labs/networking/README.md

@@ -5,7 +5,7 @@ This folder is reserved for networking-focused exercises. It can hold examples a
 ## Diagram
 
 ```mermaid
-flowchart LR
+flowchart TD
   A["networking"] --> B["Routing"]
   A --> C["DNS"]
   A --> D["Firewall and ports"]

labs/terraform/README.md

@@ -5,7 +5,7 @@ This folder is intended for Terraform experiments and infrastructure-as-code pra
 ## Diagram
 
 ```mermaid
-flowchart LR
+flowchart TD
   A["terraform"] --> B["Modules"]
   A --> C["Environment configs"]
   A --> D["Plan and apply workflows"]