Expose public/ API as submodule (#23345)

* model -> public/model

* plugin -> public/plugin

* public/model/utils -> public/utils

* platform/shared/mlog -> public/shared/mlog

* platform/shared/i18n -> public/shared/i18n

* platform/shared/markdown -> public/shared/markdown

* platform/services/timezones -> public/shared/timezones

* channels/einterfaces -> einterfaces

* expose public/ submodule

* go mod tidy

* .github: cache-dependency-path, setup-go-work

* modules-tidy for public/ too

* remove old gomodtidy

server/public/plugin/checker/render.go

@@ -0,0 +1,29 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package main
+
+import (
+	"fmt"
+	"go/token"
+	"os"
+	"path/filepath"
+)
+
+func renderWithFilePosition(fset *token.FileSet, pos token.Pos, msg string) string {
+	var cwd string
+	if d, err := os.Getwd(); err == nil {
+		cwd = d
+	}
+
+	fpos := fset.Position(pos)
+
+	filename, err := filepath.Rel(cwd, fpos.Filename)
+	if err != nil {
+		// If deriving a relative path fails for some reason,
+		// we prefer to still print the absolute path to the file.
+		filename = fpos.Filename
+	}
+
+	return fmt.Sprintf("%s:%d:%d: %s", filename, fpos.Line, fpos.Column, msg)
+}