Smoke test: read Steam's binary compat log with grep -a

On the Frame, compat_log.txt has binary bytes in it, so plain grep only said
"binary file matches" and the x86-64 launch check missed Steam's "is not
installed" line. The fake now writes that line to a compat_log.txt that starts
with a NUL, and the end-to-end test finds it the way the smoke test does.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

tests/smoke/frame_smoke.py

@@ -115,9 +115,13 @@ def status(build):
 
 
 def steam_log_lines(*patterns):
-    """Steam log lines holding any of the fixed strings (which files: not verified, so all)."""
+    """Steam log lines holding any of the fixed strings (which files: not verified, so all).
+
+    -a: compat_log.txt has binary bytes in it, and without it grep only says
+    "binary file matches" (seen on the Frame, 2026-09-27).
+    """
     pats = ' '.join(f'-e {shlex.quote(p)}' for p in patterns)
-    out = ssh(f"grep -rshF {pats} ~/.local/share/Steam/logs/ 2>/dev/null || true")
+    out = ssh(f"grep -arshF {pats} ~/.local/share/Steam/logs/ 2>/dev/null || true")
     return out.strip().splitlines()