valkyrjaio / valkyrja-java / 30593700688

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[Application] fix!: Require the config in the application kernel (#84)

# Description

The application kernel accepted a defaulted config:

```
config = new Config()
```

That default is wrong on its own terms. A config is not optional — an
application that reaches the kernel without one
is misconfigured, and it should fail loudly rather than silently boot on
the framework's defaults with the wrong
providers, the wrong namespace, the wrong data path, and `debugMode`
off. Requiring the argument turns a silent
misconfiguration into a compile-time (or constructor-time) error.

No caller in `src` or in the tests relied on the default. Every call
site already passed a config explicitly, so this
tightens the contract without changing any behavior that is actually
exercised.

## Why now

It surfaced while measuring module loading in the TypeScript port. In
TypeScript the default is not merely wrong, it is
expensive: naming `Config` in a default parameter forces an
unconditional static `import`, and `Config` names
`ApplicationComponentProvider`, which names
`ContainerComponentProvider`. So a cached application that wants none of
that loaded it anyway, purely because a default it never used mentioned
the class.

PHP and Java do not pay that cost — `use` is a compile-time alias and
the JVM resolves constant-pool entries lazily —
but the defect is the same defect in all three, so it is fixed in all
three in one batch.

Measured on the TypeScript starter application, a cached HTTP boot
serving `GET /version`:

| | modules loaded | component providers loaded |
|---|---|---|
| before | 183 | 9 |
| after, with a standalone cached config | 142 | 0 |

`Go` has no equivalent — its kernel does not reference `Config` at all.
Python and Kotlin do not exist yet.

## Breaking change

This changes a public constructor signature. Any external caller that
omitted the config must now pass one:

```
new Valkyrja(container)          // no longer compiles
new Valkyrja(container, c... (continued)

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