feat(dev): enable react-refresh for shared dev-server HMR

[joshuaellis]

Summary

• Passes reactRefreshHost to @vitejs/plugin-react so federated Studio/App modules connect their react-refresh preamble to the workbench host dev server
• When the workbench is running (federation enabled), devAction.ts computes the workbench URL and threads it through startStudioDevServer/startAppDevServer → startDevServer → getViteConfig → viteReact({reactRefreshHost})
• Enables component-level HMR across the module federation boundary

Closes SDK-1187

[github-actions]

📦 Bundle Stats — @sanity/cli

Compared against feat/workbench (e04493e2)

@sanity/cli

Metric	Value	vs feat/workbench (e04493e)
Internal (raw)	2.1 KB	-
Internal (gzip)	799 B	-
Bundled (raw)	10.95 MB	-
Bundled (gzip)	2.06 MB	-
Import time	818ms	-9ms, -1.0%

bin:sanity

Metric	Value	vs feat/workbench (e04493e)
Internal (raw)	975 B	-
Internal (gzip)	460 B	-
Bundled (raw)	9.84 MB	-
Bundled (gzip)	1.77 MB	-
Import time	2.23s	-9ms, -0.4%

🗺️ View treemap · Artifacts

Details

• Import time regressions over 10% are flagged with ⚠️
• Sizes shown as raw / gzip 🗜️. Internal bytes = own code only. Total bytes = with all dependencies. Import time = Node.js cold-start median.

📦 Bundle Stats — @sanity/cli-core

Compared against feat/workbench (e04493e2)

Metric	Value	vs feat/workbench (e04493e)
Internal (raw)	92.4 KB	-
Internal (gzip)	21.6 KB	-
Bundled (raw)	21.53 MB	-
Bundled (gzip)	3.41 MB	-
Import time	781ms	-4ms, -0.5%

🗺️ View treemap · Artifacts

Details

• Import time regressions over 10% are flagged with ⚠️
• Sizes shown as raw / gzip 🗜️. Internal bytes = own code only. Total bytes = with all dependencies. Import time = Node.js cold-start median.

📦 Bundle Stats — create-sanity

Compared against feat/workbench (e04493e2)

Metric	Value	vs feat/workbench (e04493e)
Internal (raw)	976 B	-
Internal (gzip)	507 B	-
Bundled (raw)	50.7 KB	-
Bundled (gzip)	12.6 KB	-
Import time	❌ ChildProcess denied: node	-

Details

• Import time regressions over 10% are flagged with ⚠️
• Sizes shown as raw / gzip 🗜️. Internal bytes = own code only. Total bytes = with all dependencies. Import time = Node.js cold-start median.

[claude]

Claude finished @gu-stav's task in 2m 31s —— View job

---

Review

• Read CLAUDE.md and gather context
• Get PR diff
• Review changed files
• Check changeset

---

Missing changeset

This PR modifies packages/@sanity/cli with new runtime behavior (react-refresh HMR across the module federation boundary), but no changeset file is included. A patch or minor changeset for @sanity/cli is required. Fix this →

0.0.0.0 produces an unusable reactRefreshHost URL

In devAction.ts:27:

`http://${httpHost || 'localhost'}:${workbenchPort}`

httpHost can be '0.0.0.0' (e.g. when the user passes --host 0.0.0.0). Since it's truthy, the fallback doesn't apply and the browser receives http://0.0.0.0:3333 as the react-refresh endpoint, which won't connect. The same pattern exists at line 61 for the logged workbench URL, but that's cosmetic; reactRefreshHost is consumed by the browser and the connection will silently fail. The fix is to normalize 0.0.0.0 → localhost before constructing the URL:

const resolvedHost = (!httpHost || httpHost === '0.0.0.0') ? 'localhost' : httpHost
const reactRefreshHost = closeWorkbenchServer === undefined
  ? undefined
  : `http://${resolvedHost}:${workbenchPort}`

Fix this →

[gu-stav]

@joshuaellis Fixed the lockfile in the feature branch and rebased this branch.

[github-actions]

Coverage Delta

File	Statements
packages/@sanity/cli-core/src/config/cli/schemas.ts	100.0% (±0%)
packages/@sanity/cli/src/actions/build/buildApp.ts	94.9% (±0%)
packages/@sanity/cli/src/actions/build/buildStaticFiles.ts	97.3% (+ 0.7%)
packages/@sanity/cli/src/actions/build/buildStudio.ts	97.5% (±0%)
packages/@sanity/cli/src/actions/build/getViteConfig.ts	100.0% (±0%)
packages/@sanity/cli/src/actions/dev/devAction.ts	90.0% (- 10.0%)
packages/@sanity/cli/src/actions/dev/getDevServerConfig.ts	100.0% (±0%)
packages/@sanity/cli/src/actions/dev/startAppDevServer.ts	82.3% (- 4.6%)
packages/@sanity/cli/src/actions/dev/startStudioDevServer.ts	93.3% (- 1.7%)
packages/@sanity/cli/src/actions/dev/startWorkbenchDevServer.ts	96.4% (new)
packages/@sanity/cli/src/actions/dev/writeWorkbenchRuntime.ts	100.0% (new)
packages/@sanity/cli/src/commands/dev.ts	100.0% (±0%)
packages/@sanity/cli/src/server/devServer.ts	94.1% (±0%)

Comparing 13 changed files against main @ ce65da6d7c36c721926c955d2a466dcffb25a4f1

Overall Coverage

Metric	Coverage
Statements	83.0% (- 0.0%)
Branches	73.0% (+ 0.0%)
Functions	83.2% (- 0.1%)
Lines	83.5% (±0%)