chore/update layouts in diagrams (#273)

docs/pipeline/diagrams/current/activity.mmd

@@ -1,4 +1,8 @@
-flowchart TD
+---
+config:
+    layout: elk
+---
+flowchart LR
     Start([start]) --> ParseArgs["main.cc: ParseArguments(argc, argv)"]
     ParseArgs --> ArgsValid{Arguments valid?}
     ArgsValid -- no --> LogErr[Log error / usage info] --> Stop1([stop])

docs/pipeline/diagrams/current/class.mmd

@@ -1,3 +1,8 @@
+---
+config:
+    layout: elk
+---
+
 classDiagram
     class BiergartenPipelineOrchestrator {
         -shared_ptr~ILogger~ logger_

docs/pipeline/diagrams/planned/activity.mmd

@@ -1,4 +1,9 @@
-flowchart TD
+---
+config:
+    layout: elk
+---
+
+flowchart LR
     Start([start]) --> ParseArgs["Main: ParseArguments(argc, argv)"]
     ParseArgs --> InvalidArgs{Invalid args?}
     InvalidArgs -- yes --> LogErr["spdlog::error"] --> Stop1([stop])

docs/pipeline/diagrams/planned/class.mmd

@@ -1,3 +1,7 @@
+---
+config:
+    layout: elk
+---
 classDiagram
     namespace DomainModels {
         class Location {