ast-grep[0] is a tool that uses tree-sitter[1] and a pattern language to match against code using its ast. It implements code transformation, querying, and linting.

Since clippy isn't extensible for project-specific lints, this adds a first ast-grep lint disallowing `context` as a variable name. Currently it's set to warning as usage is addressed.

To run, install ast-grep, then run `ast-grep scan`. Example output:

```
warning[no-context]: Don't name variables `context`.
    ┌─ ./crates/turbopack-ecmascript-hmr-protocol/src/lib.rs:132:9
    │
132 │     pub context: &'a str,
    │     ----^^^^^^^---------
    │
    = Use a more specific name, such as chunking_context, asset_context, etc.
```

[0] https://ast-grep.github.io
[1] https://tree-sitter.github.io/tree-sitter/

This migrates some crates away from using `context`, specifically:

- `node-file-trace`
- `turbo-tasks-build`
- `turbo-tasks-fetch`
- `turbo-tasks`
- `turbopack-build`
- `turbopack-cli-utils`
- `turbopack-cli`
- `turbopack-core`
- `turbopack-ecmascript`

This also moves the lint to `error` and ignores other failing crates.

…part-1

…part-1

…part-1

…t-grep-part-1