mpv-fourier pkgrel=7 + workflow: printf instead of yes (SIGPIPE makes pipeline fail under pipefail)

Run #70 actually succeeded at the pacman level (log shows ffmpeg
removed and ffmpeg-v4l2-request-fourier installed) but the step
exited non-zero. Cause: bash's set -o pipefail (Gitea Actions
default) sees `yes` get SIGPIPE'd when pacman closes its stdin,
yes exits 141, pipeline reports 141 → step fails.

Replace `yes y | pacman -S ...` with finite-stream printf that
exits 0 cleanly. Three y's cover all expected prompts.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.gitea/workflows/build.yml

@@ -651,8 +651,10 @@ jobs:
           pacman -Sy --noconfirm
           # Stock arch ffmpeg may already be installed from a prior fermi job;
           # pacman -S --noconfirm defaults the [y/N] conflict prompt to N.
-          # Pipe yes to accept the swap (replaces= takes care of cleanup).
-          yes y | pacman -S marfrit/ffmpeg-v4l2-request-fourier
+          # Use printf (finite stream, exits 0 cleanly) — `yes y | ...` would
+          # work but fails under bash pipefail when yes catches SIGPIPE.
+          # Three y's covers: "Remove conflict?", "Proceed?", any keyring prompt.
+          printf 'y\ny\ny\n' | pacman -S marfrit/ffmpeg-v4l2-request-fourier
 
       - name: makepkg mpv-fourier
         run: |