Reconnect streams in-process; fix for_window IPC rules

Root cause of the periodic drops (found via the new logs): mpv was
exiting cleanly (err=nil, exit 0) with its status line at 100% — i.e.
end-of-stream. UniFi Protect closes some cameras' RTSP connections every
20-40s; with --keep-open=no --idle=no mpv treated that as the file
ending, exited, and the supervisor relaunched it ~3s later (the visible
drop).

- Add --loop-file=inf so mpv reopens the stream the instant it EOFs,
  in the same process and window: sub-second recovery, no teardown,
  no supervisor bounce. The supervisor now only fires for real crashes.
- Clean up the logged exit "reason": strip ANSI escapes and skip mpv's
  transient A/V status prints, so a genuine error surfaces instead of
  "\x1b[KV: 00:00:35 / 00:00:35 (100%)". Tests cover the parsing.

Also fold in the for_window IPC fix: sway's IPC parser splits comma-
joined command lists at the top level and does not fold the continuation
into for_window (unlike the config-file parser), so the map-time
placement rules errored with "Only views can have borders" and never
installed. Register each command separately; drop the redundant
border none (the kiosk config already sets default_border none).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

internal/player/player.go

@@ -13,6 +13,7 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"regexp"
 	"strings"
 	"sync"
 	"syscall"
@@ -74,6 +75,13 @@ func (p *Player) args() []string {
 		"--cursor-autohide=always",
 		"--no-border",
 		"--fullscreen=no", // we tile via the compositor, not fullscreen
+		// Reconnect in-process when the RTSP stream ends. UniFi Protect closes
+		// a camera's RTSP connection periodically (every 20-40s on some
+		// models); without this mpv hits EOF, exits cleanly, and the
+		// supervisor relaunches it ~3s later — a visible drop. loop-file=inf
+		// reopens the same URL the instant it ends, keeping the window alive,
+		// so recovery is sub-second with no teardown.
+		"--loop-file=inf",
 		// Fit any camera into its tile regardless of the camera's aspect:
 		//  * keepaspect=yes         → letterbox the video, never crop/stretch
 		//  * keepaspect-window=no   → do NOT reshape the window to the video's
@@ -282,20 +290,45 @@ func (p *Player) Healthy() bool {
 	return reply["error"] == "success"
 }
 
-// lastLine returns the most recent non-empty stderr line mpv emitted, trimmed,
-// or "" if there was none. mpv prints its fatal error last, so the tail is the
-// useful part.
+// ansiRE matches terminal escape sequences mpv sprinkles into its output.
+var ansiRE = regexp.MustCompile(`\x1b\[[0-9;?]*[ -/]*[@-~]`)
+
+// lastLine returns the most useful recent stderr line mpv emitted: the last
+// line that is not one of mpv's periodic playback-status prints (e.g.
+// "V: 00:00:35 / 00:00:35 (100%)"), with ANSI escapes stripped. A real error
+// (connection refused, unsupported codec, 401) is what we want to surface; the
+// status line is only the fallback when nothing else was printed.
 func lastLine(w *logbuf.Writer) string {
 	if w == nil {
 		return ""
 	}
 	lines := w.Lines(0)
+	fallback := ""
 	for i := len(lines) - 1; i >= 0; i-- {
-		if s := strings.TrimSpace(lines[i]); s != "" {
-			return s
+		s := strings.TrimSpace(ansiRE.ReplaceAllString(lines[i], ""))
+		if s == "" {
+			continue
+		}
+		if fallback == "" {
+			fallback = s
+		}
+		if isStatusLine(s) {
+			continue
+		}
+		return s
+	}
+	return fallback
+}
+
+// isStatusLine reports whether s is one of mpv's transient A/V progress prints
+// rather than a substantive message.
+func isStatusLine(s string) bool {
+	for _, p := range []string{"V:", "A:", "AV:", "(Paused)", "(Buffering)"} {
+		if strings.HasPrefix(s, p) {
+			return true
 		}
 	}
-	return ""
+	return false
 }
 
 func sleep(ctx context.Context, d time.Duration) bool {