fix: use log_step (cyan) for progress messages instead of log_warn (yellow) (#534)

~1500 progress messages across 481 files were using log_warn (yellow)
for normal status updates like "Installing...", "Setting up...",
"Creating server...", etc. This made users think something was wrong
when everything was proceeding normally.

Changes:
- Replace log_warn with log_step for all progress/status messages
- Keep log_warn only for actual warnings (errors, remediation hints)
- Remove emoji from 3 sprite completion messages

Agent: ux-engineer

Co-authored-by: A <6723574+louisgv@users.noreply.github.com>

ramnode/lib/common.sh

@@ -404,7 +404,7 @@ create_server() {
     local userdata
     userdata=$(get_cloud_init_userdata | base64 -w 0 || get_cloud_init_userdata | base64)
 
-    log_warn "Creating RamNode instance '$name' (flavor: $flavor)..."
+    log_step "Creating RamNode instance '$name' (flavor: $flavor)..."
 
     local body
     body=$(_ramnode_build_server_body "$name" "$flavor" "$image_id" "$key_name" "$userdata" "${network_id:-}")
@@ -428,7 +428,7 @@ interactive_session() { ssh_interactive_session "$@"; }
 destroy_server() {
     local server_id="$1"
 
-    log_warn "Destroying server $server_id..."
+    log_step "Destroying server $server_id..."
     local response
     response=$(ramnode_compute_api DELETE "/servers/$server_id")