Spin dev components

In Spin, all components in spin.toml will make their way into a deployed application.

There are scenarios where it might be desirable to be able to execute a component locally, while in development, but definitely not in production.

An example of this is https://github.com/radu-matei/spin-kv-explorer, which can introspect the entire contents of the KV store.

I would like to investigate what a [dev_component] section could look like, that can be executed locally, but would not make its way to a production scenario by default.

For example:

[[dev_component]]
source = { url = "https://github.com/radu-matei/spin-kv-explorer/releases/download/<latest-release>/spin-kv-explorer.wasm", digest = "sha256:aaa" }
id = "kv-explorer"
# add or remove stores you want to explore here
key_value_stores = ["default"]
[component.trigger]
route = "/internal/kv-explorer/..."

Whether or not the default behavior would include or exclude dev components, first I'd like to understand if this is a feature others would find useful.

The proposal centers on spin.toml and a new [dev_component] section. Start by locating how Spin currently loads components from spin.toml, then assess whether development components should be included or excluded by default; the issue names no implementation files or tests, so the completion criteria still need to be defined.