* build: add oxfmt for code formatting and import sorting
Adds oxfmt as a devDependency alongside oxlint and wires it into the
lint pipeline. The .oxfmtrc.json config matches Electron's current JS
style (single quotes, semicolons, 2-space indent, trailing commas off,
printWidth 100) and configures sortImports with custom groups that
mirror the import/order pathGroups previously enforced by ESLint:
@electron/internal, @electron/*, and {electron,electron/**} each get
their own ordered group ahead of external modules.
- `yarn lint:fmt` runs `oxfmt --check` over JS/TS sources and is
chained into `yarn lint` so CI enforces it automatically.
- `yarn format` runs `oxfmt --write` for local fix-up.
- lint-staged invokes `oxfmt --write` on staged .js/.ts/.mjs/.cjs
files before oxlint, so formatting is applied at commit time.
The next commit applies the formatter to the existing codebase so the
check actually passes.
* chore: apply oxfmt formatting to JS and TS sources
Runs `yarn format` across lib/, spec/, script/, build/, default_app/,
and npm/ to bring the codebase in line with the .oxfmtrc.json settings
added in the previous commit. This is a pure formatting pass: import
statements are sorted into the groups defined by the config, method
chains longer than printWidth are broken, single-quoted strings
containing apostrophes are switched to double quotes, and a handful of
single-statement `if` bodies are re-wrapped and get braces added by
`oxlint --fix` to satisfy the `curly: multi-line` rule.
No behavior changes.
