fix: preserve argv boundaries in spin run and spin exec

AGENTS.md

@@ -176,9 +176,10 @@ docker run --rm \
 # lib/actions/example.sh
 #!/usr/bin/env bash
 action_example() {
-    local args=($(filter_out_spin_arguments "$@"))
-
-    # Implementation here
+    filter_out_spin_arguments "$@"
+    local args=("${SPIN_FILTERED_ARGS[@]}")
+
+    # Implementation here, using "${args[@]}" for the filtered arguments
     echo "Running example command"
 }
 ```
@@ -238,9 +239,11 @@ SPIN_ENV=production spin deploy production
 ### Argument Filtering
 
 ```bash
-# Remove Spin-specific arguments before passing to Docker
-local args=($(filter_out_spin_arguments "$@"))
-$COMPOSE_CMD up ${args[@]}
+# Remove Spin-specific arguments before passing to Docker. The filtered
+# args are returned via the SPIN_FILTERED_ARGS global.
+filter_out_spin_arguments "$@"
+local args=("${SPIN_FILTERED_ARGS[@]}")
+$COMPOSE_CMD up "${args[@]}"
 ```
 
 ### Cache Management

lib/actions/exec.sh

@@ -1,4 +1,4 @@
 #!/usr/bin/env bash
 action_exec(){
-  $COMPOSE_CMD exec $@ 
+  $COMPOSE_CMD exec "$@"
 }

lib/actions/run.sh

@@ -2,7 +2,8 @@
 action_run(){
   docker_pull_check "$@"
 
-  local args=($(filter_out_spin_arguments "$@"))
+  filter_out_spin_arguments "$@"
+  local args=("${SPIN_FILTERED_ARGS[@]}")
 
   # Run Docker Compose without dependencies. Ensure automations and S6 logging are disabled
   $COMPOSE_CMD run -e "S6_VERBOSITY=0" -e "SHOW_WELCOME_MESSAGE=false" --remove-orphans --no-deps --rm \

lib/functions.sh

@@ -459,15 +459,22 @@ export_compose_file_variable(){
   fi
 }
 
+# Filters spin-only flags out of "$@". Returns the remaining arguments via
+# the SPIN_FILTERED_ARGS global. bash can't return arrays through stdout
+# without IFS word-splitting destroying argument boundaries at the call site.
+#
+# Example usage:
+#   filter_out_spin_arguments "$@"
+#   local args=("${SPIN_FILTERED_ARGS[@]}")
+#   $COMPOSE_CMD run ... "${args[@]}"
 filter_out_spin_arguments() {
-    non_docker_args=(
+    SPIN_FILTERED_ARGS=()
+
+    local non_docker_args=(
         "--skip-pull"
         "--force-pull"
     )
 
-    # Declare an array to hold the filtered arguments
-    local filtered_args=()
-
     # Loop through all passed arguments
     for arg in "$@"; do
         local is_non_docker_arg=false
@@ -479,12 +486,9 @@ filter_out_spin_arguments() {
         done
 
         if ! $is_non_docker_arg; then
-            filtered_args+=("$arg")
+            SPIN_FILTERED_ARGS+=("$arg")
         fi
     done
-
-    # Return the filtered arguments as an array
-    echo "${filtered_args[@]}"
 }
 
 get_ansible_variable(){