valkyrjaio / sindri-ts / 30612251087

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[Config] feat: Add a command to generate a cached config (#87)

# Description

Adds `sindri generate-config <path-to-Config.ts>`, which writes a
`CachedConfig` beside an application
config. The command is opt-in and separate from `sindri generate`; data
generation does not run it.

## Why

A TypeScript application loads its whole component provider tree at
boot, even when it runs entirely on the
generated data cache. The cause is that an application config names a
component provider, and naming a class
in TypeScript forces a static `import` of that class and everything it
names. PHP and Java do not pay this,
because `use` is a compile-time alias and the JVM resolves a
constant-pool entry only when it needs the class.

A cached config removes the reference. It implements the config contract
directly, so it never imports a
framework config base, and it declares an empty provider list. Measured
on the starter application, a cached
HTTP boot that serves `GET /version`:

| | modules loaded | component providers loaded |
|---|---|---|
| the application config | 182 | 9 |
| the generated cached config | **142** | **0** |

## How it works

`ConfigSourceReader` reads the application config and returns each field
as **source text**, never as an
evaluated value. `process.env['APP_KEY']`, `process.cwd()`, and
`CliCommandName.LIST` therefore survive
exactly as the author wrote them, including expressions no static reader
could resolve.

Two shapes are read, because an application config may either extend a
framework config and pass positional
`super()` arguments, or implement the contract directly and declare
properties:

```ts
class Config extends HttpConfig { constructor() { super('App', process.cwd(), ...); } }
class Config implements HttpConfigContract { readonly namespace = 'App'; }
```

The reader also reads the base class's constructor defaults. A config
passes only the arguments it changes,
and a generated config inherits nothing, so an omitted field would... (continued)

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