feat(cli): wmill dev with per-flow proxy and responsive Dev UI

[Guilhem-lm]

Summary

• Add --path and --proxy-port flags to wmill dev for single-flow watching with reverse proxy (replaces standalone wmill flow dev)
• Add round-trip support: editing flows in the Dev UI writes changes back to disk (disabled in VS Code iframe)
• Auto-generate .claude/launch.json for flow and raw_app folders during wmill init and wmill sync pull
• Auto-detect flow path from cwd when running wmill dev inside a flow folder
• Responsive Dev page layout: horizontal split when portrait, vertical split when landscape
• Move Test Flow button into the graph pane (top-right of graph, not page)
• Hide splitter handle when only one pane is active
• Fix flow graph height clamping between minHeight and maxHeight
• Claude Desktop/CLI detection hints in wmill flow new and wmill app new

Usage Examples

1. wmill dev without proxy (preview any script/flow)

cd my-windmill-workspace
wmill dev
# Opens http://localhost:3000/dev?workspace=...
# Automatically watches the last modified file
# Edit locally → changes appear in browser

# Or target a specific path:
wmill dev --path u/admin/my_script

2. wmill dev with proxy for Claude Desktop

cd my-windmill-workspace/f/local-dev/handle_user_subscription__flow
wmill dev --proxy-port 4000
# Auto-detects the flow path from cwd
# Starts reverse proxy on port 4000
# Claude Desktop preview connects to localhost:4000

This is what the auto-generated .claude/launch.json does:

{
  "version": "0.0.1",
  "configurations": [{
    "name": "windmill",
    "runtimeExecutable": "bash",
    "runtimeArgs": ["-c", "wmill dev --proxy-port ${PORT:-4000}"],
    "port": 4000,
    "autoPort": true
  }]
}

App demo:

Snake.mov

Flow demo:

flow.demo.mov

3. wmill app new + open Claude session

wmill app new
# Creates a new raw app scaffold with .claude/launch.json
# Detects Claude CLI/Desktop and prints instructions:
#   → "cd <app-path> && claude" (if CLI installed)
#   → "Open Claude Desktop with <app-path> as root folder" (if Desktop installed)
# Claude Desktop can then use /preview to launch the dev server

Test plan

• Run wmill dev --path f/some/flow --proxy-port 4000 and verify proxy forwards to Windmill
• Run wmill dev inside a flow folder and verify auto-detection works
• Edit flow in Dev UI and verify changes written back to local files
• Run wmill init and verify .claude/launch.json created in flow and raw_app folders
• Run wmill sync pull and verify launch.json generated for new flows and apps
• Run wmill flow new and verify Claude hints are printed
• Resize Dev page window: wide → side-by-side split, tall → top/bottom split
• Open an aiagent step and verify no splitter handle is visible
• Open a large flow and verify the graph respects max height

🤖 Generated with Claude Code

[cloudflare-workers-and-pages]

Deploying windmill with    Cloudflare Pages

Latest commit:	0ac96b9
Status:	✅  Deploy successful!
Preview URL:	https://92ccc3e3.windmill.pages.dev
Branch Preview URL:	https://glm-add-local-dev-proxy-v2.windmill.pages.dev

View logs