Killing the ftl interactive command causes panic

[wesbillman]

Start ftl dev --recreate. Wait for echo and time to deploy, then CTRL+C to kill it.

ftl dev --recreate

info:controller0: Deployed dpl-echo-43mar6x7owpoqa01
info: All modules deployed in 13.974872167s, watching for changes...
echo:  ✅  time:  ✅
panic: channel not subscribed

goroutine 69 [running]:
github.com/alecthomas/types/pubsub.(*Topic[...]).Unsubscribe(0x104b437a0, 0x14000666e00)
	/Users/wesbillman/go/pkg/mod/github.com/alecthomas/[email protected]/pubsub/pubsub.go:139 +0xb4
github.com/TBD54566975/ftl/internal/buildengine.(*Engine).watchForModuleChanges.func2()
	/Users/wesbillman/dev/ftl/internal/buildengine/engine.go:369 +0x34
github.com/TBD54566975/ftl/internal/buildengine.(*Engine).watchForModuleChanges(0x140006eb2c0, {0x104b0f0d0, 0x14000a1a690}, 0x1dcd6500)
	/Users/wesbillman/dev/ftl/internal/buildengine/engine.go:411 +0xec0
github.com/TBD54566975/ftl/internal/buildengine.(*Engine).Dev(...)
	/Users/wesbillman/dev/ftl/internal/buildengine/engine.go:337
main.(*devCmd).Run.func2()
	/Users/wesbillman/dev/ftl/frontend/cli/cmd_dev.go:102 +0x5cc
golang.org/x/sync/errgroup.(*Group).Go.func1()
	/Users/wesbillman/go/pkg/mod/golang.org/x/[email protected]/errgroup/errgroup.go:78 +0x54
created by golang.org/x/sync/errgroup.(*Group).Go in goroutine 1
	/Users/wesbillman/go/pkg/mod/golang.org/x/[email protected]/errgroup/errgroup.go:75 +0x98