fix: enclose rounded preferred timings in EDID ranges

docs/verification.md

@@ -112,7 +112,11 @@ The probe applies the tracked patch to four relevant source files in a temporary
 directory, compiles the actual EDID and virtio GPU generator functions with a
 small dependency harness, and decodes the result. It checks 60/75 Hz fallback,
 144 Hz configuration, a conflicting 60 Hz frontend request, resized dimensions,
-checksums and monitor ranges. At 1920×1080/144000 mHz the preferred timing is
+checksums and monitor ranges. It also checks the supported vertical-refresh
+boundaries: 1920×1080/50000 mHz and 1280×800/255000 mHz. Range endpoints
+use floor/ceiling of the encoded timing after pixel-clock rounding, so the
+49.998895 Hz lower-boundary timing is included by a 49 Hz minimum. Normal
+automatic 60/75 Hz cases retain the legacy 50–125 Hz range. At 1920×1080/144000 mHz the preferred timing is
 143.997231 Hz after EDID clock rounding. This is an advertised guest mode,
 not measured frame delivery or proof of a 144 Hz physical output.