feat(styles): add Aura Theme primary variants (#1177)

#### Description

This PR: Adds a new style based on [Aura
Theme](https://github.com/daltonmenezes/aura-theme)

#### Assets

<img width="1388" height="871" alt="aura-chroma-preview"
src="https://github.com/user-attachments/assets/0471c9f7-708b-4e73-a935-1058197d66ef"
/>

feat: improve tracing

`--trace` now outputs a JSON structure with tracing information, eg.

```
{"lexer":"markdown","state":"root","rule":15,"pos":0,"elapsedMs":0.022875}
{"lexer":"markdown","state":"root","rule":15,"pos":1,"elapsedMs":0.002667}
{"lexer":"markdown","state":"root","rule":15,"pos":2,"elapsedMs":0.001833}
{"lexer":"markdown","state":"root","rule":15,"pos":3,"elapsedMs":0.002166}
{"lexer":"markdown","state":"root","rule":15,"pos":4,"elapsedMs":0.002125}
```

This should generally be much more amenable to analysis, eg. convenient
filtering using jq to help track down hotspots:

```
chroma --trace docs.md 2>&1 > /dev/null | jq 'select(. | .elapsedMs > 0.1)' | less
```

feat: WASM playground

feat: support for dark mode in chromad

- Upgraded Bulma.
- Default to monokai if browser is in dark mode, monokailight if not.

fix: downgrade gorilla/csrf temporarily

1.7.3 broke everything

fix: a bunch of styles did not correctly fallback to parent styles

Fixes #1076

Fix Gleam lexer (#1072)

I made the Gleam lexer *dumber* (that is, more acquiescent), but it
fixes #1054 and still passes the tests.

chore: clean up Makefile

Add WebVTT lexer (#707) (#1032)

Implements a WebVTT lexer (#707)

lexers/cue: support CUE attributes (#961)

Currently the following CUE results in the chroma lexer producing an
error token for the '@':

    value: string @go(Value)

This code is, however, valid CUE. '@go' is an attributes.

This change adds lexer support for attributes in CUE.