Replace Prettier with BiomeJS for webview client formatting

[Copilot]

Ports the formatter migration from bumps/bumps#434 into this repo, scoped to the refl1d/webview/client frontend.

Config

• New refl1d/webview/client/biome.json — 2-space indent, 120-char line width, double quotes, ES5 trailing commas; linter disabled (ESLint owns that); schema pinned to 2.4.13 matching bumps PR
• Deleted refl1d/webview/client/prettier.config.js

package.json

• Added @biomejs/biome ^2.4.13
• Removed: prettier, eslint-plugin-prettier, @vue/eslint-config-prettier, eslint-config-prettier, @ianvs/prettier-plugin-sort-imports, prettier-plugin-css-order, prettier-plugin-jsdoc
• Scripts updated:

  - "format": "prettier --write src",
  - "test:lint": "eslint src && prettier --check ...",
  + "format": "biome format --write src",
  + "test:format": "biome format src/",
  + "test:lint": "eslint src",

eslint.config.js

• Removed eslint-plugin-prettier/recommended, @vue/eslint-config-prettier, prettier/prettier rule, and "prettier" compat extend
• Disabled Vue stylistic rules that conflict with Biome (vue/html-indent, vue/max-attributes-per-line, vue/html-self-closing, etc.)

CI (.github/workflows/test-webview-client.yaml)

• Renamed existing job comment from "formatted and linted" → "linted"
• Added dedicated test-format job running bun run test:format

Pre-commit (.pre-commit-config.yaml)

• Added biome-format hook via biomejs/pre-commit v0.6.1 targeting .(vue|js|ts|…|json) files

Formatter-driven source changes

Biome reformatted ternary expressions in DataView.vue and SimpleBuilder.vue (condition-first style vs. Prettier's value-first).

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• biomejs.dev
  • Triggering command: /usr/bin/curl curl -s -o /dev/null -w %{http_code} REDACTED (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

Port the formatter migration pattern from merged PR bumps/bumps#434 into the reflectometry/refl1d repository, but scope it to this repo’s current frontend/webview setup.

Repository: reflectometry/refl1d
Base branch: master

Goal

• Replace the frontend Prettier-based formatting setup with BiomeJS for the Refl1D webview client, following the same overall intent as bumps/bumps#434.
• Preserve or improve existing lint/test workflow behavior.
• Open a pull request with the resulting changes.

Relevant current files in reflectometry/refl1d

• .pre-commit-config.yaml
• .github/workflows/test-webview-client.yaml
• refl1d/webview/client/package.json
• refl1d/webview/client/eslint.config.js
• refl1d/webview/client/prettier.config.js
• likely a new refl1d/webview/client/biome.json or repo-level biome.json, whichever best fits this repo

Reference PR behavior to mirror
From bumps/bumps#434, the important behavior was:

• add Biome config
• remove Prettier config/dependencies from the web client
• update package scripts so formatting uses Biome and linting is separated from formatting
• update ESLint config to stop integrating with Prettier
• add a dedicated format check job in GitHub Actions
• keep stylistic conflicts between ESLint/Vue rules and Biome under control
• apply any necessary formatting-only code changes caused by the formatter switch

Repository-specific guidance

1. Inspect the current Refl1D frontend setup rather than blindly copying the bumps PR.
2. Update refl1d/webview/client/package.json to:
   • replace Prettier usage in scripts with Biome equivalents
   • add @biomejs/biome
   • remove Prettier-only dependencies that are no longer needed
   • keep lint and formatting responsibilities separated, similar to the bumps PR
   • add a test:format script if appropriate for CI
3. Update refl1d/webview/client/eslint.config.js to remove Prettier integration:
   • remove eslint-plugin-prettier/recommended
   • remove @vue/eslint-config-prettier / prettier extends if present
   • remove prettier/prettier rule wiring
   • if necessary, disable Vue stylistic rules that conflict with Biome formatting
4. Remove refl1d/webview/client/prettier.config.js if it becomes obsolete.
5. Add Biome configuration in the most sensible location for this repo. Prefer matching the practical behavior of the bumps PR, but adapt includes/excludes to Refl1D’s file layout.
6. Update .github/workflows/test-webview-client.yaml to separate lint and format checks, mirroring the bumps PR’s CI shape.
7. Update .pre-commit-config.yaml if needed so frontend formatting/linting continues to work coherently with the new toolchain.
8. Run/apply formatter-driven updates to affected frontend files as needed.

Important constraints

• Keep the scope focused on the webview client / formatter migration. Do not include unrelated dependency upgrades or refactors unless required to make the migration work.
• Do not reproduce unrelated changes from existing open PRs in this repository.
• There are already open formatter-related PRs in reflectometry/refl1d (for example Switch to biome for frontend formatting #342, Switch to Oxlint/Oxfmt #353, Biomejs again, with setting more similar to before #354). Avoid duplicating unrelated broad refactors from those PRs. This task should be a clean, minimal migration aligned with bumps/bumps#434.
• Prefer minimal, reviewable changes.

Suggested PR title

• Replace Prettier with BiomeJS for webview client formatting

Suggested PR body points

• switch webview client formatting from Prettier to BiomeJS
• remove Prettier integration from ESLint
• add format check to webview client CI
• update formatting scripts/config accordingly

The following is the prior conversation context from the user's chat exploration (may be truncated):

User: Create a PR that does the same thing done in @bumps/bumps/pull/434 for the reflectometry/refl1d repository, replacing the prettier formatter with biomejs

Assistant: I’ve started the pull request creation process and we’re waiting for your response to the GitHub confirmation dialog before I can continue.

This pull request was created from Copilot chat.

[bmaranville]

This was somewhat a test if copilot could make a simple PR given clear instructions. I don't know that it saved me any time over doing it myself, as it missed a couple things and didn't follow directions exactly. (it went off-script in that it didn't copy the structure from the bumps PR exactly, so the pre-commit throws errors without having a biome.json both in the project and client root)