switch flow diagram to top-down layout to avoid horizontal scroll

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: AlexF4Dev

README.md

@@ -50,26 +50,17 @@ CI runs automatically on push to main and PRs with 5 parallel validation jobs.
 ## How It Works
 
 ```mermaid
-flowchart LR
-    subgraph trigger ["1. Trigger (ci-pr-trigger)"]
-        A["Cron schedule"] --> B["Query GHCR API\n+ semver filter"]
-        B --> C{"New tags?"}
-    end
-
-    subgraph pr ["2. PR Creation (ci-create-release-pr)"]
-        D["Read current\ntags from .env"] --> E{"Changed?"}
-        E -- Yes --> F["Update .env\nvia sed"]
-        F --> G["Create PR +\nauto-merge"]
-    end
-
-    subgraph deploy ["3. Deployment"]
-        H["PR merges"] --> I["paths filter"]
-        I -- Match --> J["Copy files\nto server"]
-        J --> K["docker compose\nup"]
-    end
-
-    C -- Yes --> D
-    G --> H
+flowchart TD
+    A["Cron schedule"] --> B["Query GHCR API + semver filter"]
+    B --> C{"New tags?"}
+    C -- Yes --> D["Read current tags from .env"]
+    D --> E{"Changed?"}
+    E -- Yes --> F["Update .env via sed"]
+    F --> G["Create PR + auto-merge"]
+    G --> H["PR merges to deploy branch"]
+    H --> I{"paths filter"}
+    I -- Match --> J["Copy files to server"]
+    J --> K["docker compose up"]
     K --> L["Slack notify"]
 ```