Add Mermaid chart

Author: maxvp

src/content/docs/cloudflare-one/policies/gateway/http-policies/file-sandboxing.mdx

@@ -15,6 +15,32 @@ In addition to [anti-virus (AV) scanning](/cloudflare-one/policies/gateway/http-
 
 When your users download a file, Gateway will first scan the file with AV scanning. If AV scanning detects malware, Gateway will block the download and log the result. If AV scanning does not detect malware, Gateway will send the file to the sandbox. While in the sandbox, Gateway will monitor the inputs and outputs of the file. While the files are quarantined, Gateway will present a scanning page to your users. If a file passes scanning, Gateway will release the file from quarantine and download it to your user's device. If the file contains malware, Gateway will block the request and log the match as a Block decision in your [HTTP logs](/cloudflare-one/insights/logs/gateway-logs/#http-logs).
 
+```mermaid
+flowchart TD
+    A(["User starts file download"]) --> B["File sent to AV scanner"]
+    B --> C["Malicious file detected?"]
+    C -- Yes --> D["Download blocked"]
+    C -- No --> G["File sent to sandbox"]
+    G --> n1["First time file appears?"]
+    K["Malicious activity detected?"] -- Yes --> N["Download blocked"]
+    K -- No --> n3["Download allowed"]
+    n1 -- Yes --> n2["Interstitial page displayed for user during scan"]
+    n2 --> K
+    n1 -- No --> K
+
+    B@{ shape: subproc}
+    C@{ shape: diam}
+    D@{ shape: terminal}
+    n1@{ shape: diam}
+    K@{ shape: diam}
+    N@{ shape: terminal}
+    n3@{ shape: terminal}
+    n2@{ shape: display}
+    style D stroke:#D50000
+    style N stroke:#D50000
+    style n3 stroke:#00C853
+```
+
 ## Get started
 
 To begin quarantining downloaded files, turn on file sandboxing: