[Config] Update the 'Instance configuration' guide to using a new config

[andreyaksenov]

Product: Tarantool
Since: 3.0
Root document:

• https://www.tarantool.io/en/doc/latest/book/admin/instance_config/
• https://www.tarantool.io/en/doc/latest/reference/tooling/tt_cli/configuration/#app-section
• https://www.tarantool.io/en/doc/latest/reference/reference_lua/other/

SME: @ Totktonada

See also:

• Cluster configuration: https://docs.d.tarantool.io/en/doc/3.0/concepts/configuration/#starting-tarantool-instances
• https://docs.d.tarantool.io/en/doc/3.0/concepts/configuration/configuration_code/

Example

Unpacked application structure (packaged using tt pack):

/home/testuser/myapp
├── bin
│   ├── tarantool
│   └── tt
├── instances.enabled
│   └── sharded_cluster -> ../sharded_cluster
├── sharded_cluster
│   ├── .rocks
│   │   └── share
│   │       └── ...
│   ├── config.yaml
│   ├── instances.yaml
│   ├── router.lua
│   ├── sharded_cluster-scm-1.rockspec
│   └── storage.lua
└── tt.yaml

See also: https://docs.google.com/document/d/1fOaD9_084CiQ_PrlpNrvjhrK9P3zaKgRf54fU8ZKJ4I/edit

[andreyaksenov]

TT_PRELOAD note: also works for tt

TT_PRELOAD=before_myapp.lua tt start application

Looks like this section should be moved to Starting and stopping instances.

[andreyaksenov]

https://docs.d.tarantool.io/en/doc/3.0/book/admin/instance_config/