feat: Add Hyperstack OpenCode support (#191)

Implement hyperstack/opencode.sh script that provisions a Hyperstack VM
and installs OpenCode with OpenRouter integration.

Agent: gap-filler-hyperstack-4

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

hyperstack/opencode.sh

@@ -0,0 +1,46 @@
+#!/bin/bash
+set -eo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" 2>/dev/null && pwd)"
+# shellcheck source=hyperstack/lib/common.sh
+if [[ -f "${SCRIPT_DIR}/lib/common.sh" ]]; then
+    source "${SCRIPT_DIR}/lib/common.sh"
+else
+    eval "$(curl -fsSL https://raw.githubusercontent.com/OpenRouterTeam/spawn/main/hyperstack/lib/common.sh)"
+fi
+
+log_info "OpenCode on Hyperstack"
+echo ""
+
+ensure_hyperstack_api_key
+ensure_ssh_key
+
+VM_NAME=$(get_vm_name)
+ENVIRONMENT=$(get_environment_name)
+create_vm "${VM_NAME}" "${ENVIRONMENT}"
+verify_server_connectivity "${HYPERSTACK_VM_IP}"
+
+log_warn "Installing OpenCode..."
+run_server "${HYPERSTACK_VM_IP}" "$(opencode_install_cmd)"
+log_info "OpenCode installed"
+
+echo ""
+if [[ -n "${OPENROUTER_API_KEY:-}" ]]; then
+    log_info "Using OpenRouter API key from environment"
+else
+    OPENROUTER_API_KEY=$(get_openrouter_api_key_oauth 5180)
+fi
+
+log_warn "Setting up environment variables..."
+inject_env_vars_ssh "${HYPERSTACK_VM_IP}" upload_file run_server \
+    "OPENROUTER_API_KEY=${OPENROUTER_API_KEY}"
+
+echo ""
+log_info "Hyperstack VM setup completed successfully!"
+log_info "VM: ${VM_NAME} (ID: ${HYPERSTACK_VM_ID}, IP: ${HYPERSTACK_VM_IP})"
+echo ""
+
+log_warn "Starting OpenCode..."
+sleep 1
+clear
+interactive_session "${HYPERSTACK_VM_IP}" "source ~/.zshrc && opencode"