Initial commit: Null DRM Official

Capture, decrypt, and restream toolkit with compiled-in app modules
(RTE, TG4, BBC), on-device MITM proxy, streamd control plane, and www.
BBC module.yaml is published (clear streams); other module values stay local.

apps/pkg/session/stream.go

@@ -0,0 +1,66 @@
+package session
+
+import (
+	"encoding/json"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+)
+
+// Stream is a streamd-ready description of one playable channel, as produced by
+// a provider catalog lookup. MPD holds the manifest URL whatever its type.
+type Stream struct {
+	Name         string   `json:"name"`
+	Title        string   `json:"title"`
+	App          string   `json:"app"`
+	Channel      string   `json:"channel"`
+	MPD          string   `json:"mpd"`
+	Key          string   `json:"key"`
+	Keys         []string `json:"keys,omitempty"`
+	PSSH         string   `json:"pssh,omitempty"`
+	PrimaryKID   string   `json:"primary_kid,omitempty"`
+	HeadersJSON  string   `json:"headers_json"`
+	Rewriter     string   `json:"rewriter"`
+	LicenseURL   string   `json:"license_url,omitempty"`
+	AccountID    string   `json:"account_id,omitempty"`
+	VideoID      string   `json:"video_id,omitempty"`
+	PlaybackURL  string   `json:"playback_url,omitempty"`
+	ManifestType string   `json:"manifest_type,omitempty"`
+}
+
+// WriteStream writes outputs/<app>/<stamp>/{session.json,mpd.txt,license.txt,…}
+// and refreshes outputs/<app>/latest. The app name comes from the caller so no
+// provider name is baked in here.
+func WriteStream(root, app string, info Stream) (string, error) {
+	stamp := time.Now().Format("20060102-150405")
+	dir := filepath.Join(root, "outputs", app, stamp)
+	if err := os.MkdirAll(dir, 0o755); err != nil {
+		return "", err
+	}
+	raw, err := json.MarshalIndent(info, "", "  ")
+	if err != nil {
+		return "", err
+	}
+	if err := os.WriteFile(filepath.Join(dir, "session.json"), append(raw, '\n'), 0o644); err != nil {
+		return "", err
+	}
+	write := func(name, val string) {
+		if val == "" {
+			return
+		}
+		_ = os.WriteFile(filepath.Join(dir, name), []byte(val+"\n"), 0o644)
+	}
+	write("mpd.txt", info.MPD)
+	write("license.txt", info.LicenseURL)
+	write("pssh.txt", info.PSSH)
+	write("key.txt", info.Key)
+	write("pid.txt", info.VideoID)
+	if len(info.Keys) > 0 {
+		write("keys.txt", strings.Join(info.Keys, "\n"))
+	}
+	latest := filepath.Join(root, "outputs", app, "latest")
+	_ = os.RemoveAll(latest)
+	_ = copyDir(dir, latest)
+	return dir, nil
+}