Add Jsonnet native functions.

[fujiwara]

like ecspresso.

local tfstate = std.native('tfstate');
local env = std.native('env');
local must_env = std.native('must_env');
local ssm = std.native('ssm');
local caller = std.native('caller_identity');
{
  Environment: {
    Variables: {
      FOO: ssm('/hello/foo'), # lookup ssm
    },
  },
  FunctionName: 'hello',
  Handler: 'index.js',
  MemorySize: std.parseInt(env('MEMORY', '128')), // read env
  Role: 'arn:aws:iam::%s:role/LambdaBasicExecutionRole' % caller().Account, // resolve caller AWS Account ID
  Runtime: 'nodejs20.x',
  Timeout: 5,
  TracingConfig: {
    Mode: 'PassThrough',
  },
  VpcConfig: {
    SubnetIds: [
      tfstate('aws_subnet.lambda["az-a"].id'), // lookup tfstate
      tfstate('aws_subnet.lambda["az-b"].id'),
    ],
    SecurityGroupIds: [
      tfstate('aws_security_group.internal["%s"].id' % must_env('WORLD')),
    ],
  },
}