hyperstack: split 3335-line monolith into lib/hyperstack/ modules

Extracts all classes from hyperstack.rb into focused library files:
- lib/hyperstack/config.rb    — ConfigLoader + Config (TOML loading, validation)
- lib/hyperstack/state.rb     — StateStore + PrefixedOutput (JSON state, threaded output)
- lib/hyperstack/client.rb    — HyperstackClient (REST API + retry logic)
- lib/hyperstack/wireguard.rb — LocalWireGuard (wg1.conf peer management, /etc/hosts)
- lib/hyperstack/provisioning.rb — ProvisioningScripts + RemoteProvisioner (SSH bootstrap)
- lib/hyperstack/manager.rb   — Manager (VM lifecycle orchestration)
- lib/hyperstack/watcher.rb   — VllmWatcher (Prometheus + GPU dashboard)
- lib/hyperstack/cli.rb       — CLI (OptionParser command dispatch)

hyperstack.rb becomes a 46-line entry point with require_relative calls.
All files pass `ruby -c` syntax check and `--help` runs correctly.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

1 files changed, 140 insertions, 0 deletions

diff --git a/lib/hyperstack/client.rb b/lib/hyperstack/client.rb
new file mode 100644
index 0000000..b7b4a6b
--- /dev/null
+++ b/lib/hyperstack/client.rb
@@ -0,0 +1,140 @@
+# frozen_string_literal: true
+
+require 'json'
+require 'net/http'
+require 'openssl'
+require 'socket'
+require 'timeout'
+
+module HyperstackVM
+  # HTTP client for the Hyperstack (NexGenCloud) REST API.
+  # Handles authentication, JSON encoding/decoding, and retry logic with exponential back-off.
+  class HyperstackClient
+    def initialize(base_url:, api_key:)
+      @base_uri = URI(base_url)
+      @api_key = api_key
+    end
+
+    def list_environments
+      response = request(:get, '/core/environments')
+      response.fetch('environments', [])
+    end
+
+    def list_keypairs
+      response = request(:get, '/core/keypairs')
+      response.fetch('keypairs', [])
+    end
+
+    def list_flavors
+      response = request(:get, '/core/flavors')
+      Array(response['data']).flat_map do |entry|
+        Array(entry['flavors']).map do |flavor|
+          flavor.merge(
+            'region_name' => flavor['region_name'] || entry['region_name'],
+            'gpu' => flavor['gpu'] || entry['gpu']
+          )
+        end
+      end
+    end
+
+    def list_images
+      response = request(:get, '/core/images')
+      Array(response['images']).flat_map do |entry|
+        Array(entry['images']).map do |image|
+          image.merge(
+            'region_name' => image['region_name'] || entry['region_name'],
+            'type' => image['type'] || entry['type']
+          )
+        end
+      end
+    end
+
+    def list_vms
+      response = request(:get, '/core/virtual-machines')
+      response.fetch('instances', [])
+    end
+
+    def get_vm(vm_id)
+      response = request(:get, "/core/virtual-machines/#{vm_id}")
+      response.fetch('instance', nil)
+    end
+
+    def create_vm(payload)
+      request(:post, '/core/virtual-machines', payload)
+    end
+
+    def delete_vm(vm_id)
+      request(:delete, "/core/virtual-machines/#{vm_id}")
+    end
+
+    def create_vm_rule(vm_id, payload)
+      request(:post, "/core/virtual-machines/#{vm_id}/sg-rules", payload)
+    end
+
+    def delete_vm_rule(vm_id, rule_id)
+      request(:delete, "/core/virtual-machines/#{vm_id}/sg-rules/#{rule_id}")
+    end
+
+    private
+
+    def request(method, path, payload = nil)
+      uri = @base_uri.dup
+      uri.path = "#{@base_uri.path}#{path}"
+
+      request = case method
+                when :get
+                  Net::HTTP::Get.new(uri)
+                when :post
+                  Net::HTTP::Post.new(uri)
+                when :delete
+                  Net::HTTP::Delete.new(uri)
+                else
+                  raise Error, "Unsupported HTTP method: #{method}"
+                end
+
+      request['accept'] = 'application/json'
+      request['api_key'] = @api_key
+      if payload
+        request['content-type'] = 'application/json'
+        request.body = JSON.generate(payload)
+      end
+
+      retries_left = 4
+      begin
+        response = Net::HTTP.start(
+          uri.host,
+          uri.port,
+          use_ssl: uri.scheme == 'https',
+          open_timeout: 30,
+          read_timeout: 120
+        ) { |http| http.request(request) }
+
+        parse_response(response)
+      rescue Timeout::Error, Errno::ECONNREFUSED, Errno::ECONNRESET,
+             Errno::EHOSTUNREACH, Errno::ENETUNREACH,
+             SocketError, OpenSSL::SSL::SSLError, Net::OpenTimeout => e
+        raise Error, "Hyperstack API request failed for #{path}: #{e.message}" if retries_left <= 0
+
+        retries_left -= 1
+        delay = (4 - retries_left) * 5
+        warn "API request to #{path} failed (#{e.class}: #{e.message}), retrying in #{delay}s (#{retries_left} left)..."
+        sleep delay
+        retry
+      end
+    end
+
+    def parse_response(response)
+      body = response.body.to_s
+      payload = body.empty? ? {} : JSON.parse(body)
+
+      if response.code.to_i >= 400 || payload['status'] == false
+        message = payload['message'] || payload['error_reason'] || response.message
+        raise Error, "Hyperstack API error (HTTP #{response.code}): #{message}"
+      end
+
+      payload
+    rescue JSON::ParserError => e
+      raise Error, "Failed to parse Hyperstack API response: #{e.message}"
+    end
+  end
+end