chore: migrate from Biome to oxlint + oxfmt

[MarioCadenas]

What

Migrate the repo's lint/format toolchain from Biome to the oxc (VoidZero) stack:

• oxlint for linting (.oxlintrc.json)
• oxfmt for formatting + import sorting (.oxfmtrc.json)

@biomejs/biome and biome.json are removed.

Why

Ecosystem alignment (the repo already runs rolldown-vite, a VoidZero fork) and speed. Both configs were migrated from biome.json via oxfmt --migrate=biome, then tuned for behavior parity.

Changes

• Add .oxlintrc.json / .oxfmtrc.json.
• Rewrite lint / format / check (+ docs:*) scripts and lint-staged for oxlint + oxfmt.
• Rename tools/format-with-biome.ts → tools/format-generated.ts (formats generated files with oxfmt); update its 3 importers.
• Translate the live biome-ignore suppressions to oxlint-disable; drop 64 dead noExplicitAny suppressions (the rule was already off).
• Reorganize imports repo-wide via oxfmt sortImports (the Biome organizeImports equivalent). Order-critical side-effect imports — reflect-metadata, dotenv/config, CSS — are preserved (oxfmt treats bare imports as partition boundaries).

Parity decisions

Biome did lint + format + import-org in one binary; oxc splits these. To keep this a behavior-preserving swap rather than a lint-bar change:

• package.json sorting disabled (sortPackageJson: false) — oxfmt would otherwise reorder keys, which Biome never did.
• oxlint's stricter-than-Biome correctness rules are disabled with a documented // Re-enable and fix in a follow-up block in .oxlintrc.json (no-unsafe-optional-chaining, typescript/no-this-alias, react/exhaustive-deps, react/no-array-index-key, several unicorn/*, etc.). These flag ~65 pre-existing, working sites that Biome's CI was green over; tightening them is deliberately left as a follow-up.
• The @databricks/sdk-experimental import boundary (no-restricted-imports) is preserved, including the workspace-client / lakebase overrides.

Accepted loss

• CSS is no longer linted/formatted — oxc does not handle CSS (8 .css files). This is the only capability lost vs Biome.

Verification

• oxlint → exit 0 (3 advisory no-unused-vars warnings, non-failing — pre-existing, left as-is)
• oxfmt --check → exit 0 (idempotent)
• pnpm -r typecheck → pass (7 projects)
• pnpm generate:types → all generated files written and oxfmt-clean
• Import boundary guardrail → fires with the correct message
• pnpm test → 3788 passed, 1 skipped, 0 failed

Follow-ups

• Optionally re-enable the deferred stricter oxlint rules and fix the flagged sites.
• Optionally add a dedicated CSS formatter if CSS formatting is still wanted.

[github-actions]

📦 Bundle size report

Compared against bundle-size-baseline.json (main).

@databricks/appkit

npm tarball (packed): 840 KB (+167 B) — gzipped download (dist + bin; excludes release-only docs/NOTICE).

dist	raw	gzip
JS (runtime)	869 KB	303 KB
Type declarations	315 KB	109 KB (-9 B)
Source maps	1.7 MB (+159 B)	566 KB (+143 B)
Other	11 KB	3.7 KB
Total	2.9 MB (+159 B)	982 KB (+134 B)

Per-entry composition (own code — deps external (as shipped))

Entry	Initial (gz)	Lazy (gz)	Total (gz)	node_modules (min)	Own code (min)
.	88 KB	2.5 KB	91 KB	external	288 KB
./beta	49 KB	457 B	49 KB	external	143 KB
./type-generator	21 KB	0 B	21 KB	external	61 KB

Chunks:

Entry	Chunk	Load	Size (gz)
.	index.js	initial	84 KB
.	utils.js	initial	4.0 KB
.	remote-tunnel-manager.js	lazy	2.5 KB
./beta	beta.js	initial	33 KB
./beta	stream-manager.js	initial	5.8 KB
./beta	wide-event-emitter.js	initial	3.2 KB
./beta	databricks.js	initial	3.0 KB
./beta	configuration.js	initial	2.1 KB
./beta	service-context.js	initial	1.3 KB
./beta	client.js	initial	434 B
./beta	client-options.js	initial	220 B
./beta	supervisor-api.js	lazy	192 B
./beta	databricks.js	lazy	142 B
./beta	index.js	lazy	123 B
./type-generator	index.js	initial	21 KB

@databricks/appkit-ui

npm tarball (packed): 342 KB (-291 B) — gzipped download (dist + bin; excludes release-only docs/NOTICE).

dist	raw	gzip
JS (runtime)	390 KB	130 KB (+1 B)
Type declarations	228 KB	83 KB
Source maps	752 KB (-334 B)	247 KB (-197 B)
CSS	16 KB (-462 B)	3.2 KB (-90 B)
Total	1.4 MB (-796 B)	464 KB (-286 B)

Per-entry composition (consumer bundle — deps bundled, peerDeps external)

Entry	Initial (gz)	Lazy (gz)	Total (gz)	node_modules (min)	Own code (min)
./js	5.3 KB	49 KB	55 KB	208 KB	14 KB
./js/beta	20 B	0 B	20 B	0 B	0 B
./react	432 KB (+127 B)	49 KB	480 KB (+127 B)	1.3 MB	175 KB
./react/beta	1.0 KB	0 B	1.0 KB	0 B	1.9 KB

Chunks:

Entry	Chunk	Load	Size (gz)
./js	index.js	initial	5.2 KB
./js	chunk	initial	120 B
./js	apache-arrow	lazy	49 KB
./js/beta	beta.js	initial	20 B
./react	index.js	initial	430 KB
./react	tslib	initial	2.1 KB
./react	apache-arrow	lazy	49 KB
./react/beta	beta.js	initial	1.0 KB

[github-actions]

🤖 AppKit PR bot

🔬 Run evals

Start an eval for this PR from the evals-monitor app: Go to Evals Monitor →

📦 Try this PR's app template

Scaffolds a new app from this PR's SDK build. Run it in any folder (requires the GitHub CLI — gh auth login — and the Databricks CLI):

gh run download 32022037310 -R databricks/appkit -n appkit-template-0.61.1-pr.25c8dd8-chore-migrate-biome-to-oxc-538 -D appkit-pr-538 \
&& unzip -o "appkit-pr-538/appkit-template-0.61.1-pr.25c8dd8-chore-migrate-biome-to-oxc-538.zip" -d "appkit-pr-538" \
&& databricks apps init --template "appkit-pr-538"

The template pins @databricks/appkit and @databricks/appkit-ui to tarballs built from this branch, so the scaffolded app runs against this PR's code.