Add efficient process wait utility function

Add wait_for_process() that uses kill -0 instead of ps -p
for checking if a process is running. This is more efficient
as kill -0 only checks process existence without spawning
a new process like ps would.

Includes optional spinner for visual feedback during waits.

#7

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

proxDoc.sh

@@ -128,6 +128,24 @@ get_disk_list() {
     echo "$DISK_LIST"
 }
 
+# Efficient process wait with optional spinner
+# Usage: wait_for_process $pid [delay]
+# Uses kill -0 instead of ps -p for efficiency
+wait_for_process() {
+    local pid="$1"
+    local delay="${2:-0.1}"
+    local spinner='|/-\'
+    local i=0
+
+    while kill -0 "$pid" 2>/dev/null; do
+        printf "\r%c " "${spinner:i++%${#spinner}:1}"
+        sleep "$delay"
+    done
+    printf "\r  \r"  # Clear spinner
+    wait "$pid"
+    return $?
+}
+
 ###################
 # System Information Functions
 ###################