Generate js and curl snippets using templates (#1291)

PR built on top of
#1273.

This is supposed to be the last PR refactoring inference snippets
:hear_no_evil:
`python.ts`, `curl.ts` and `js.ts` have been merged into a single
`getInferenceSnippets.ts` which handles snippet generations for all
languages and all providers at once. Here is how to use it:

```ts
import { snippets } from "@huggingface/inference";

const generatedSnippets = snippets.getInferenceSnippets(model, "api_token", provider, providerModelId, opts);
```

it returns a list `InferenceSnippet[]` defined as 

```ts
export interface InferenceSnippet {
    language: InferenceSnippetLanguage; // e.g. `python`, `curl`, `js`
    client: string; // e.g. `huggingface_hub`, `openai`, `fetch`, etc.
    content: string;
}
```

---

### How to review?

It's hard to track all atomic changes made to the inference snippets but
the best way IMO to review this PR is to check the generated snippets in
the tests. Many inconsistencies in the URLs, sent parameters and
indentation have been fixed.

---

### What's next?

- [x] get #1273
approved
- [ ] merge this one
(#1291) into
#1273
- [ ] merge #1273
- [ ] open PR in moon-landing to adapt to new interface (basically use
`snippets.getInferenceSnippets` instead of `python.getPythonSnippets`,
etc)
- [ ] open PR to fix hub-docs automatic generation
- [ ] fully ready for Inference Providers documentation!

---------

Co-authored-by: Simon Brandeis <[email protected]>

Author: Wauplin