Enable func-names

ESLint's [`func-names`][1] allows us to enforce or disallow the use of named function expressions. This could be useful for requiring function expressions to have a name, if the name cannot be assigned automatically in an ES6 environment:

[1]:https://eslint.org/docs/rules/func-names

```js
"func-names": ["error", "as-needed", { "generators": "as-needed" }],
```

Start by locating the shared ESLint configuration and review how existing rules are declared. Enable the `func-names` rule with the documented `as-needed` and generator options, then verify that the configuration loads and enforces the intended named-function behavior.

Written by the indexing model from the issue text.