feat: add raw func and allow using funcs in output name

examples/system-info.md

@@ -0,0 +1,29 @@
+---
+output: sys-report-{{ raw "date --iso-8601" }}.md
+---
+
+# 💥 System Information Report for {{ sh "hostname" }}
+
+* **Hostname**: {{ sh "hostname" }}
+* **Username**: {{ sh "whoami" }}
+* **Uptime**: {{ sh "uptime -p" }}
+* **System**: {{ sh "uname -a" }}
+* **CPU**: {{ sh "uname -m" }} — {{ sh "nproc" }} cores
+* **IP Address**: {{ sh "hostname -I || ip a | grep inet" }}
+* **Default Gateway**: {{ sh "ip route | grep default || netstat -rn | grep default" }}
+
+---
+
+## 🧠 Memory Usage
+
+{{ shell "free -h" }}
+
+---
+
+## 📉 Disk Usage
+
+{{ shell "df -h /" }}
+
+---
+
+Generated on: {{ sh "date" }}