Add cloudstack_network_acl_ruleset resource with comprehensive ACL management

This commit introduces a new resource for managing network ACL rules with several
improvements over the legacy cloudstack_network_acl_rule resource.

Key Features:
- Declarative ruleset management with efficient in-place updates
- Rules identified by rule_number (natural key) instead of list position
- Eliminates spurious diffs when modifying individual rules
- Optional managed mode to delete out-of-band rules
- Concurrent rule operations with proper synchronization
- Support for protocol transitions (e.g., TCP to ICMP)

Technical Implementation:
- Uses TypeSet with Optional+Computed pattern for rules
- CustomizeDiff function to suppress spurious diffs by comparing rules via rule_number
- Three-phase update strategy: delete, update, create (preserves UUIDs)
- Managed mode uses dummy rules to track out-of-band changes
- Helper function buildRuleFromAPI() to eliminate code duplication
- Safe type assertions to prevent runtime panics
- Proper validation placement in verifyACLRuleParams

Legacy Resource Updates:
- Deprecated cloudstack_network_acl_rule with migration guidance
- Added deprecation notice to documentation
- Maintains backward compatibility

Testing:
- 12 comprehensive acceptance tests covering all scenarios
- Tests for basic CRUD, managed mode, protocol transitions, field changes
- Import functionality testing
- Spurious diff prevention verification
- All tests passing

Documentation:
- Complete user guide with multiple examples
- Clear migration path from legacy resource
- Accurate field descriptions (no unsupported features mentioned)

Author: bhouse-nexthop

cloudstack/provider.go

@@ -130,6 +130,7 @@ func Provider() *schema.Provider {
 			"cloudstack_network":                        resourceCloudStackNetwork(),
 			"cloudstack_network_acl":                    resourceCloudStackNetworkACL(),
 			"cloudstack_network_acl_rule":               resourceCloudStackNetworkACLRule(),
+			"cloudstack_network_acl_ruleset":            resourceCloudStackNetworkACLRuleset(),
 			"cloudstack_nic":                            resourceCloudStackNIC(),
 			"cloudstack_physical_network":               resourceCloudStackPhysicalNetwork(),
 			"cloudstack_pod":                            resourceCloudStackPod(),