The shop PC's UI had never once been run

`wails build` had never been executed against this project - CLAUDE.md
says so plainly - so every screen the shop floor actually touches was
unreviewed. Running it found why nobody had.

fyne.io/systray's nativeLoop must own the main thread on macOS, a Cocoa
requirement, and Wails already holds it. Starting both kills the process
with a SIGTRAP inside cgo before a single pixel is drawn. On Windows,
which is what ships, a tray on its own goroutine is fine - so the one
platform the whole team develops on was the one platform that could not
open the app, and the UI went unlooked-at as a result.

BEHAVISION_NO_TRAY runs the window without the tray, the same escape
hatch BEHAVISION_ALLOW_PLAINTEXT_MQTT already is for the broker.
Deliberately an environment variable and NOT a GOOS check: a build that
quietly drops the tray is how a shop PC ends up with no control surface
at all, and it would fail where nobody is watching. The guard is on stop()
as well, because systray.Quit() on a systray that never started is not a
no-op in v1.12.2 - it would turn closing the window into a crash on exit,
the failure most likely to be shrugged off as "it closed, fine".

go.mod gains the indirect dependencies the darwin build pulls in. No
version moved: the committed list was written by a windows-only build,
which never resolves that part of the Wails tree.

Verified: GOOS=windows build, go vet, and the agent suite all still pass,
and the packaged .app runs.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Qiy5iKfz4L8S4vRaYPBdaU

.gitignore

@@ -55,3 +55,10 @@ node_modules/
 
 # Backups of .env made when editing camera credentials.
 /.env.bak-*
+
+# Generated by the wails CLI on every dev run and build, not source.
+# NOT /desktop/build/ as a whole: appicon.png, darwin/ and windows/ under it
+# are the Wails project scaffolding (icon, Info.plist, manifest) that a
+# reproducible Windows build needs. Only the compiled output is ignored.
+/desktop/frontend/wailsjs/
+/desktop/frontend/package.json.md5

desktop/go.mod

@@ -14,16 +14,34 @@ require (
 )
 
 require (
+	github.com/bep/debounce v1.2.1 // indirect
 	github.com/eclipse/paho.mqtt.golang v1.4.3 // indirect
+	github.com/go-ole/go-ole v1.2.6 // indirect
 	github.com/godbus/dbus/v5 v5.1.0 // indirect
+	github.com/google/uuid v1.3.0 // indirect
 	github.com/gorilla/websocket v1.5.0 // indirect
+	github.com/jchv/go-winloader v0.0.0-20210711035445-715c2860da7e // indirect
+	github.com/labstack/echo/v4 v4.10.2 // indirect
+	github.com/labstack/gommon v0.4.0 // indirect
 	github.com/leaanthony/go-ansi-parser v1.6.0 // indirect
+	github.com/leaanthony/gosod v1.0.3 // indirect
 	github.com/leaanthony/slicer v1.6.0 // indirect
 	github.com/leaanthony/u v1.1.0 // indirect
+	github.com/mattn/go-colorable v0.1.13 // indirect
+	github.com/mattn/go-isatty v0.0.19 // indirect
+	github.com/pkg/browser v0.0.0-20210911075715-681adbf594b8 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/rivo/uniseg v0.4.4 // indirect
+	github.com/samber/lo v1.38.1 // indirect
+	github.com/tkrajina/go-reflector v0.5.6 // indirect
+	github.com/valyala/bytebufferpool v1.0.0 // indirect
+	github.com/valyala/fasttemplate v1.2.2 // indirect
 	github.com/wailsapp/go-webview2 v1.0.16 // indirect
+	github.com/wailsapp/mimetype v1.4.1 // indirect
+	golang.org/x/crypto v0.23.0 // indirect
+	golang.org/x/exp v0.0.0-20230522175609-2e198f4a06a1 // indirect
 	golang.org/x/net v0.25.0 // indirect
 	golang.org/x/sync v0.1.0 // indirect
 	golang.org/x/sys v0.20.0 // indirect
+	golang.org/x/text v0.15.0 // indirect
 )

desktop/go.sum

@@ -3,6 +3,7 @@ fyne.io/systray v1.12.2/go.mod h1:RVwqP9nYMo7h5zViCBHri2FgjXF7H2cub7MAq4NSoLs=
 github.com/bep/debounce v1.2.1 h1:v67fRdBA9UQu2NhLFXrSg0Brw7CexQekrBwDMM8bzeY=
 github.com/bep/debounce v1.2.1/go.mod h1:H8yggRPQKLUhUoqrJC1bO2xNya7vanpDl7xR3ISbCJ0=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/eclipse/paho.mqtt.golang v1.4.3 h1:2kwcUGn8seMUfWndX0hGbvH8r7crgcJguQNCyp70xik=
 github.com/eclipse/paho.mqtt.golang v1.4.3/go.mod h1:CSYvoAlsMkhYOXh/oKyxa8EcBci6dVkLCbo5tTC1RIE=
@@ -20,6 +21,7 @@ github.com/labstack/echo/v4 v4.10.2 h1:n1jAhnq/elIFTHr1EYpiYtyKgx4RW9ccVgkqByZaN
 github.com/labstack/echo/v4 v4.10.2/go.mod h1:OEyqf2//K1DFdE57vw2DRgWY0M7s65IVQO2FzvI4J5k=
 github.com/labstack/gommon v0.4.0 h1:y7cvthEAEbU0yHOf4axH8ZG2NH8knB9iNSoTO8dyIk8=
 github.com/labstack/gommon v0.4.0/go.mod h1:uW6kP17uPlLJsD3ijUYn3/M5bAxtlZhMI6m3MFxTMTM=
+github.com/leaanthony/debme v1.2.1 h1:9Tgwf+kjcrbMQ4WnPcEIUcQuIZYqdWftzZkBr+i/oOc=
 github.com/leaanthony/debme v1.2.1/go.mod h1:3V+sCm5tYAgQymvSOfYQ5Xx2JCr+OXiD9Jkw3otUjiA=
 github.com/leaanthony/go-ansi-parser v1.6.0 h1:T8TuMhFB6TUMIUm0oRrSbgJudTFw9csT3ZK09w0t4Pg=
 github.com/leaanthony/go-ansi-parser v1.6.0/go.mod h1:+vva/2y4alzVmmIEpk9QDhA7vLC5zKDTRwfZGOp3IWU=
@@ -30,6 +32,7 @@ github.com/leaanthony/slicer v1.6.0 h1:1RFP5uiPJvT93TAHi+ipd3NACobkW53yUiBqZheE/
 github.com/leaanthony/slicer v1.6.0/go.mod h1:o/Iz29g7LN0GqH3aMjWAe90381nyZlDNquK+mtH2Fj8=
 github.com/leaanthony/u v1.1.0 h1:2n0d2BwPVXSUq5yhe8lJPHdxevE2qK5G99PMStMZMaI=
 github.com/leaanthony/u v1.1.0/go.mod h1:9+o6hejoRljvZ3BzdYlVL0JYCwtnAsVuN9pVTQcaRfI=
+github.com/matryer/is v1.4.0 h1:sosSmIWwkYITGrxZ25ULNDeKiMNzFSr4V/eqBQP0PeE=
 github.com/matryer/is v1.4.0/go.mod h1:8I/i5uYgLzgsgEloJE1U6xx5HkBQpAZvepWuujKwMRU=
 github.com/mattn/go-colorable v0.1.11/go.mod h1:u5H1YNBxpqRaxsYJYSkiCWKzEfiAb1Gb520KVy5xxl4=
 github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
@@ -42,6 +45,7 @@ github.com/pkg/browser v0.0.0-20210911075715-681adbf594b8 h1:KoWmjvw+nsYOo29YJK9
 github.com/pkg/browser v0.0.0-20210911075715-681adbf594b8/go.mod h1:HKlIX3XHQyzLZPlr7++PzdhaXEj94dEiJgZDTsxEqUI=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
 github.com/rivo/uniseg v0.4.4 h1:8TfxU8dW6PdqD27gjM8MVNuicgxIjxpm4K7x4jp8sis=
@@ -50,6 +54,8 @@ github.com/samber/lo v1.38.1 h1:j2XEAqXKb09Am4ebOg31SpvzUTTs6EN3VfgeLUhPdXM=
 github.com/samber/lo v1.38.1/go.mod h1:+m/ZKRl6ClXCE2Lgf3MsQlWfh4bn1bz6CXEOxnEXnEA=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
+github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
 github.com/tkrajina/go-reflector v0.5.6 h1:hKQ0gyocG7vgMD2M3dRlYN6WBBOmdoOzJ6njQSepKdE=
 github.com/tkrajina/go-reflector v0.5.6/go.mod h1:ECbqLgccecY5kPmPmXg1MrHW585yMcDkVl6IvJe64T4=
 github.com/valyala/bytebufferpool v1.0.0 h1:GqA5TC/0021Y/b9FG4Oi9Mr3q7XYx6KllzawFIhcdPw=
@@ -92,3 +98,5 @@ golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGm
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

desktop/tray.go

@@ -3,6 +3,7 @@ package main
 import (
 	"context"
 	"fmt"
+	"os"
 	"sync"
 	"time"
 
@@ -10,6 +11,25 @@ import (
 	"github.com/wailsapp/wails/v2/pkg/runtime"
 )
 
+// BEHAVISION_NO_TRAY runs the window with no tray icon.
+//
+// It exists so the UI can be looked at on a Mac. fyne.io/systray's nativeLoop
+// must own the main thread on macOS - a Cocoa requirement, not a library
+// choice - and Wails already holds it, so starting both kills the process with
+// a SIGTRAP inside cgo before a single screen is drawn. On Windows, which is
+// what ships, a tray on its own goroutine is fine. That asymmetry is why this
+// went unnoticed for so long: the shop-floor UI had never once been run on the
+// platform it is developed on, so every screen in it was unreviewed.
+//
+// Deliberately an environment variable and NOT a GOOS check. A build that
+// quietly drops the tray on some platform is how a shop PC ends up with no
+// control surface at all - the one thing a shop manager has - and it would
+// fail exactly where nobody is watching. Nothing is skipped unless a person
+// asked for it, by name, on this run.
+const noTrayEnv = "BEHAVISION_NO_TRAY"
+
+func trayDisabled() bool { return os.Getenv(noTrayEnv) != "" }
+
 // tray is the always-present control surface. Wails v2 has no systray of its
 // own, so this drives fyne.io/systray alongside the window.
 //
@@ -32,6 +52,9 @@ type tray struct {
 func newTray(a *App) *tray { return &tray{app: a, quit: make(chan struct{})} }
 
 func (t *tray) start(ctx context.Context) {
+	if trayDisabled() {
+		return
+	}
 	t.once.Do(func() {
 		go systray.Run(func() { t.onReady(ctx) }, func() {})
 	})
@@ -43,6 +66,13 @@ func (t *tray) stop() {
 	default:
 		close(t.quit)
 	}
+	// systray.Quit() on a systray that was never started is not a no-op in
+	// v1.12.2, so the guard has to be on both ends or quitting the window
+	// takes the process down with it - a crash on exit, which is the failure
+	// most likely to be shrugged off as "it closed, fine".
+	if trayDisabled() {
+		return
+	}
 	systray.Quit()
 }