Improve hooks API and separate to input/output

At the moment, we don't have a clear distinction between the input and the output of every hook.
We can implement this concept by changing the signature of every hook function (breaking change for sure), to be something like:

```ts
type OnParse = (readonly api: { context: TInputContext }) => ({ contextExtension: TOutputContext });
```

### Improved input/output `context` types

Related: https://github.com/dotansimha/envelop/issues/439

This way, we can use TS conditional types to do TS checks for enforcing some fields in the return value, based on other conditions.

[Here's an example for enforcing context extensions based on `TOutputContext` value](https://www.typescriptlang.org/play#code/MYewdgzgLgBApgWwA5QJ4HkCuUnYMLhRwAeUAyqggEYgA2MAvDBdXQBQBEiKG2uUBMEVIsatDgEoAUFID0AKnlSY8mAElIRAIYATGCABmMTBACWYAOYwABiSJgdg4VGswAFnABOcGFoi+kUwAaGAB3H2AtMBgocK0AaxiPGG8oTE9ogDctWkwfHThgWi1PLShTcBgqVBgdEHMrUGRTWi8YYA9geIgAOhhlVTIQGHN2vx9DX2juNHbCOxg2MBBYCDhYaqSfEzaAWgA+GAQ4KP8oNzKYVBB0mCRci1HTCDAAclgLessY4bs4By2cyEdgkYQiUV8tFoIFCKXW6TADRgHEy9R0HCCAyq2BG0Uia0BO08MDWUDOyRuOBxoGBpB+JJAx3aJigjJiqCQcBC4TG0zABhAnmAPlSCKRHBpzgAoqR-mZwBwelisWYCjBlkQAFzqJLmRKmKCvfwIQURVoQthRPQGTBgYDlcA5AD8oNZRwSPnOPjcIBA3VqXys5zK3PB0SQnhAVByNRyEF+kHSPlMCAQ2C0VBaBpqHm8TpgBYGsikJCQgtgaE5MHQYAACiU1gAxMAAHgAKhp+E47CE21gqQJ5nSmJW4JMZrwB92RJQxIcmJbAtqAN5A5zajtgLtD2AAXxgoIYhz7fHwO-gsocZw5Y6ME-729p5FndBg+dRpj0K+UBbXdhl9jymA2r1p45Q5O2D5nk+hyyLIMC1pG0ZULQNQ8hAPqYLQeg7MilzmtA+hgD48RwKgHD6MS8bHOcSLmNAJx6JMoHgbQTpSLuADcMgKEoKgwDKWjIK0MAAIzagAcsMkoLM8JLrCEGrqnAcB6G6-wCkKIrwhkSIyXSfyQBUkBFlINKEUQ0DidWdYNnAzYtqu3gAI7agASnAzl5NAu7zosWiBIehzLlxcjwb+MAAHrsXIihYoJwk+AATNqUqeJGnghPpsChH46orHCaQZKpSoqMW5kVnA0ApTZoFNq2Tmee5nneVAu4hKuwDpN4QgAKprJ4ag6NqYCYNQbS+Yw-mBYwwWhXBEVRTFvHxcQQn3D4ADM2rZLQn6mRVMRVVA221XZDmNa5MAeV5x3tTAnXdf8UD9V4Q0jWNVATX5i6mEFD0-gWooZADi2-tlAFysZ35g2DXXpc9r2DcNYkAAyA4tu4Y1j83hb+0VSEAA)

### Type Inference

we can infer the return type of `onParse` if it extends `context`, and then change the `InputContext` of `onValidate` to be `ParseContextExtensions & TInputContext`.

This way we can enforce that a plugin actually populates all keys defined in `OutputContext`.

### Core Indicators

We can also use this `hook(readonly input) -> output` to allow plugins to return "indictators" (or, actual values) to the core, and effet how Envelop manages the flow.

Here's an example for short-circuit `onParse` and skip validations:

```ts
{
onParse(api) {
const result = parse(api.source);
return {
parseResult: result, // set the result
shortCircuit: true, // skip all other `onParse` functions,
skipValidatatePhase: true // relevanat for cache plugins
};
}
}
```

### Immutability?

This way we can implement immutability for the context building (so every hook call is similar to `immer` flow, where you return the modifications, and set it in a immutable way)

Start by locating the current hook signatures and the onParse and onValidate entry points. Compare how context is passed between hooks with the proposed input/output types, inferred context extensions, and core indicators. Done means the hook API and context flow support the described type checks and returned control values across the relevant hooks.

Written by the indexing model from the issue text.