refactor: split the command dispatch out of main.go

Completes the restructuring started when main() became run() int. main.go goes
from 1217 lines to 130: global option handling, config loading, signal setup,
and a dispatch switch that delegates to one function per command.

The command bodies move to cmd_rip.go (url, file, id), cmd_search.go (search,
lastfm), cmd_config.go (config, database) and cmd_smoke.go (the developer smoke
commands), each taking (ctx, cfg, gopts, args) and returning an exit code.

They also stop reading the process global. Previously run() did

    os.Args = append([]string{os.Args[0], gopts.command}, gopts.commandArgs...)

and the arms then indexed back into os.Args[2:], os.Args[5:] and so on, so the
already-parsed options were round-tripped through os.Args. The arms now take
the parsed gopts.commandArgs directly, which is a uniform index shift of two
(os.Args[5:] -> args[3:], len(os.Args) < 5 -> len(args) < 3).

No behaviour change. Verified by running each command's argument validation and
help path against the built binary, plus the existing suite.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

cmd/rip/cmd_rip.go

@@ -0,0 +1,200 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"strings"
+
+	"streamrip-go/internal/app"
+	"streamrip-go/internal/config"
+)
+
+// Commands that queue media and rip it: url, file and id.
+
+func cmdURL(ctx context.Context, cfg *config.Config, gopts globalOptions, args []string) int {
+	if len(args) < 1 {
+		printCommandHelp(os.Stdout, "url")
+		return 2
+	}
+
+	mainApp, err := app.New(cfg)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "app init error: %v\n", err)
+		return 1
+	}
+	defer func() { _ = mainApp.Close() }()
+
+	rawArgs := make([]string, 0, len(args))
+	ignoreDB := false
+	for _, arg := range args {
+		if arg == "--force" || arg == "--ignore-db" {
+			ignoreDB = true
+			continue
+		}
+		rawArgs = append(rawArgs, arg)
+	}
+	mainApp.IgnoreDB = ignoreDB || gopts.noDB
+
+	added := 0
+	for _, raw := range rawArgs {
+		if addURLToQueue(ctx, mainApp, raw) {
+			added++
+		}
+	}
+
+	if added == 0 {
+		fmt.Println("nothing to rip")
+		return 0
+	}
+
+	if err = mainApp.Resolve(ctx); err != nil {
+		fmt.Fprintf(os.Stderr, "resolve error: %s\n", errorWithActionableHint(err, gopts))
+		return 1
+	}
+	if err = mainApp.Rip(ctx); err != nil {
+		fmt.Fprintf(os.Stderr, "rip error: %s\n", errorWithActionableHint(err, gopts))
+		return 1
+	}
+	fmt.Printf("url rip complete (%d item(s))\n", added)
+
+	return 0
+}
+
+func cmdFile(ctx context.Context, cfg *config.Config, gopts globalOptions, args []string) int {
+	if len(args) < 1 {
+		printCommandHelp(os.Stdout, "file")
+		return 2
+	}
+
+	ignoreDB := false
+	for _, arg := range args[1:] {
+		switch arg {
+		case "--force", "--ignore-db":
+			ignoreDB = true
+		default:
+			fmt.Fprintf(os.Stderr, "option error: unknown option %q\n", arg)
+			return 2
+		}
+	}
+
+	content, err := os.ReadFile(args[0])
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "read file error: %v\n", err)
+		return 1
+	}
+
+	idItems, urls, repeated, jsonInput, err := parseFileInput(content)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "file parse error: %v\n", err)
+		return 2
+	}
+
+	mainApp, err := app.New(cfg)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "app init error: %v\n", err)
+		return 1
+	}
+	defer func() { _ = mainApp.Close() }()
+	mainApp.IgnoreDB = ignoreDB || gopts.noDB
+
+	added := 0
+	if jsonInput {
+		fmt.Printf("detected json file. loading %d item(s)\n", len(idItems))
+		for _, item := range idItems {
+			if err = mainApp.AddByID(ctx, item.Source, item.MediaType, item.ID); err != nil {
+				fmt.Printf("add failed: source=%s type=%s id=%s err=%v\n", item.Source, item.MediaType, item.ID, err)
+				continue
+			}
+			added++
+		}
+	} else {
+		if repeated > 0 {
+			fmt.Printf("found %d repeated url(s)\n", repeated)
+		}
+		fmt.Printf("detected list of urls. loading %d item(s)\n", len(urls))
+		for _, raw := range urls {
+			if addURLToQueue(ctx, mainApp, raw) {
+				added++
+			}
+		}
+	}
+
+	if added == 0 {
+		fmt.Println("nothing to rip")
+		return 0
+	}
+
+	if err = mainApp.Resolve(ctx); err != nil {
+		fmt.Fprintf(os.Stderr, "resolve error: %s\n", errorWithActionableHint(err, gopts))
+		return 1
+	}
+	if err = mainApp.Rip(ctx); err != nil {
+		fmt.Fprintf(os.Stderr, "rip error: %s\n", errorWithActionableHint(err, gopts))
+		return 1
+	}
+	fmt.Printf("file rip complete (%d item(s))\n", added)
+
+	return 0
+}
+
+func cmdID(ctx context.Context, cfg *config.Config, gopts globalOptions, args []string) int {
+	if len(args) < 3 {
+		printCommandHelp(os.Stdout, "id")
+		return 2
+	}
+
+	source := strings.ToLower(strings.TrimSpace(args[0]))
+	mediaType := strings.ToLower(strings.TrimSpace(args[1]))
+	itemID := strings.TrimSpace(args[2])
+
+	opts, err := parseSmokeOptions(args[3:], 0, 4)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "option error: %v\n", err)
+		return 2
+	}
+	if opts.qualitySet {
+		switch source {
+		case "qobuz":
+			if opts.quality < 1 {
+				fmt.Fprintf(os.Stderr, "quality error: qobuz quality must be 1-4\n")
+				return 2
+			}
+			cfg.Session.Qobuz.Quality = opts.quality
+		case "tidal":
+			cfg.Session.Tidal.Quality = opts.quality
+		case "yandex":
+			cfg.Session.Yandex.Quality = opts.quality
+		case "beatport":
+			if opts.quality < 1 {
+				fmt.Fprintf(os.Stderr, "quality error: beatport quality must be 1-4\n")
+				return 2
+			}
+			cfg.Session.Beatport.Quality = opts.quality
+		}
+	}
+
+	mainApp, err := app.New(cfg)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "app init error: %v\n", err)
+		return 1
+	}
+	defer func() { _ = mainApp.Close() }()
+	mainApp.IgnoreDB = opts.ignoreDB || gopts.noDB
+
+	if err = mainApp.AddByID(ctx, source, mediaType, itemID); err != nil {
+		fmt.Fprintf(os.Stderr, "add error: %v\n", err)
+		return 1
+	}
+	if err = mainApp.Resolve(ctx); err != nil {
+		fmt.Fprintf(os.Stderr, "resolve error: %s\n", errorWithActionableHint(err, gopts))
+		return 1
+	}
+	if err = mainApp.Rip(ctx); err != nil {
+		fmt.Fprintf(os.Stderr, "rip error: %s\n", errorWithActionableHint(err, gopts))
+		return 1
+	}
+	fmt.Printf("id rip complete: source=%s type=%s id=%s\n", source, mediaType, itemID)
+
+	return 0
+}