chore: migrate mail themes to shared framework and locked upstream inputs

tools/cli/upstream.go

@@ -0,0 +1,31 @@
+package cli
+
+import (
+	"fmt"
+	"gitea-mail-templates/tools/upstream"
+	"github.com/urfave/cli/v2"
+)
+
+func UpstreamCommand() *cli.Command {
+	return &cli.Command{Name: "upstream", Usage: "Prepare, synchronize or verify locked official build inputs", Subcommands: []*cli.Command{
+		{Name: "prepare", Usage: "Download missing immutable cache files from gitea.lock.json", Flags: []cli.Flag{&cli.StringFlag{Name: "root", Value: ".."}}, Action: func(c *cli.Context) error { _, err := upstream.Prepare(c.Context, c.String("root")); return err }},
+		{Name: "sync", Usage: "Review a new Gitea tag and regenerate the lock and cache", Flags: []cli.Flag{&cli.StringFlag{Name: "tag", Required: true}, &cli.StringFlag{Name: "root", Value: ".."}}, Action: func(c *cli.Context) error { return upstream.SyncRoot(c.Context, c.String("tag"), c.String("root")) }},
+		{Name: "verify", Usage: "Verify cached inputs against the repository lock offline", Flags: []cli.Flag{&cli.StringFlag{Name: "root", Value: ".."}}, Action: func(c *cli.Context) error {
+			s, err := upstream.LoadPinned(c.String("root"))
+			if err != nil {
+				return err
+			}
+			missing, err := upstream.MissingKeys(s)
+			if err != nil {
+				return err
+			}
+			fmt.Printf("[PASS] %s: %d mail files, %d languages\n", s.Lock.Tag, len(s.Templates), len(s.Locales))
+			for _, lang := range s.Languages() {
+				if keys := missing[lang]; len(keys) > 0 {
+					fmt.Printf("[FALLBACK] %s -> en-US: %v\n", lang, keys)
+				}
+			}
+			return nil
+		}},
+	}}
+}