chore: use plugin.Start for python language plugin (#3193)

Justfile

@@ -80,9 +80,9 @@ build-python-plugin: build-zips build-protos
   shopt -s extglob
 
   if [ "${FTL_DEBUG:-}" = "true" ]; then
-    go build -o "{{RELEASE}}/ftl-language-python" -tags release -gcflags=all="-N -l" -ldflags "-X github.com/TBD54566975/ftl.Version={{VERSION}} -X github.com/TBD54566975/ftl.Timestamp={{TIMESTAMP}}" "./python-runtime/cmd"
+    go build -o "{{RELEASE}}/ftl-language-python" -tags release -gcflags=all="-N -l" -ldflags "-X github.com/TBD54566975/ftl.Version={{VERSION}} -X github.com/TBD54566975/ftl.Timestamp={{TIMESTAMP}}" "./python-runtime/cmd/ftl-language-python"
   else
-    mk "{{RELEASE}}/ftl-language-python" : !(build|integration) -- go build -o "{{RELEASE}}/ftl-language-python" -tags release -ldflags "-X github.com/TBD54566975/ftl.Version={{VERSION}} -X github.com/TBD54566975/ftl.Timestamp={{TIMESTAMP}}" "./python-runtime/cmd"
+    mk "{{RELEASE}}/ftl-language-python" : !(build|integration) -- go build -o "{{RELEASE}}/ftl-language-python" -tags release -ldflags "-X github.com/TBD54566975/ftl.Version={{VERSION}} -X github.com/TBD54566975/ftl.Timestamp={{TIMESTAMP}}" "./python-runtime/cmd/ftl-language-python"
   fi
 
 export DATABASE_URL := "postgres://postgres:secret@localhost:15432/ftl?sslmode=disable"

python-runtime/cmd/ftl-language-python/main.go

@@ -0,0 +1,23 @@
+package main
+
+import (
+	"context"
+
+	"github.com/TBD54566975/ftl/backend/protos/xyz/block/ftl/v1/language/languagepbconnect"
+	"github.com/TBD54566975/ftl/common/plugin"
+	pythonplugin "github.com/TBD54566975/ftl/python-runtime/python-plugin"
+)
+
+func main() {
+	plugin.Start(
+		context.Background(),
+		"ftl-language-python",
+		createService,
+		languagepbconnect.LanguageServiceName,
+		languagepbconnect.NewLanguageServiceHandler,
+	)
+}
+
+func createService(ctx context.Context, config any) (context.Context, *pythonplugin.Service, error) {
+	return ctx, pythonplugin.New(), nil
+}

scripts/ftl-language-python

@@ -4,4 +4,4 @@ ftldir="$(dirname "$(readlink -f "$0")")/.."
 name="ftl-language-python"
 dest="${ftldir}/build/devel"
 mkdir -p "$dest"
-(cd "${ftldir}/python-runtime/cmd" && "${ftldir}/bin/go" build -ldflags="-s -w -buildid=" -o "$dest/${name}" ./) && exec "$dest/${name}" "$@"
+(cd "${ftldir}/python-runtime/cmd/ftl-language-python" && "${ftldir}/bin/go" build -ldflags="-s -w -buildid=" -o "$dest/${name}" ./) && exec "$dest/${name}" "$@"