Chore: [#389] Migrate from ESLint/Prettier to Oxlint/Oxfmt

[RomiC]

Closes #389

Replace ESLint and Prettier with the Rust-based Oxc toolchain — Oxlint (linter, 50-100x faster) and Oxfmt (formatter).

Changes

• Dependencies: removed 5 ESLint/Prettier packages, added oxlint@1.76.0 and oxfmt@0.61.0
• Configs: added oxlint.config.ts (rules mapped from the old ESLint config) and oxfmt.config.ts (preserves old Prettier settings: printWidth 120, singleQuote, no trailing commas; YAML keeps double quotes)
• Scripts: lint/lint:fix → oxlint, format/format:check → oxfmt
• Hooks: enabled husky hooks — pre-commit runs npx lint-staged (oxlint --fix + oxfmt), pre-push runs npm test
• CI: added format:check step to both npm-test and npm-publish workflows
• Removed: eslint.config.js, .prettierrc and all ESLint/Prettier deps

[greptile-apps]

Greptile Summary

This PR replaces ESLint/Prettier with the Rust-based Oxc toolchain (Oxlint + Oxfmt), removes 5 legacy dev-dependencies, and wires the new tools into lint-staged, husky hooks, and CI.

• Config migration: oxlint.config.ts maps the old ESLint rule set to Oxlint equivalents with category-based defaults (correctness/suspicious as error, perf as warn); oxfmt.config.ts faithfully reproduces all previous Prettier settings — all options including arrowParens, bracketSpacing, and trailingComma are confirmed supported by oxfmt.
• Hooks & CI: lint-staged invokes the binaries directly (oxlint --fix, oxfmt) so staged-file arguments are forwarded correctly; both CI workflows gain a format:check step between lint and test.
• Source: src/index.ts disable comment updated from eslint-disable-next-line to oxlint-disable-next-line.

Confidence Score: 5/5

Safe to merge — this is a pure tooling swap with no changes to library logic or public API.

All changed files are dev-tooling configuration. The new configs are well-formed, all oxfmt options are verified as supported, and the lint-staged setup correctly passes staged files to the binaries. No functional code changes outside of reformatting and updating a disable comment.

Files Needing Attention: No files require special attention.

Important Files Changed

Filename	Overview
oxlint.config.ts	New oxlint config with plugins and category-based rules; overrides correctly disable import/no-default-export for *.config.ts files.
oxfmt.config.ts	New oxfmt config preserving Prettier settings; all options (arrowParens, bracketSpacing, trailingComma, etc.) are valid and supported by oxfmt.
package.json	ESLint/Prettier deps removed, oxlint and oxfmt added; lint-staged calls binaries directly (not via npm run), ensuring staged file arguments are forwarded correctly.
src/index.ts	ESLint disable comment updated to oxlint-disable-next-line; file reformatted by oxfmt with no functional changes.
.github/workflows/npm-test.yml	Added format:check step between lint and test; correct placement ensures formatting failures fail fast.
.github/workflows/npm-publish.yml	Added format:check step to match npm-test workflow; publish gate now verifies lint, formatting, and tests.
.husky/pre-commit	Simple pre-commit hook running npx lint-staged; correct since lint-staged is a devDependency.
.husky/pre-push	Pre-push hook runs npm test (which includes pretest build step); correct gate for push.

_{Reviews (3): Last reviewed commit: "Chore: [#389] Remove `any` from combineQ..." | Re-trigger Greptile}