fix(grub): put ttyAMA0 last so it's the primary console on ARM64

Kernel takes the last `console=` argument as primary (where init's stdout/stderr
land). The previous order had ttyS0 last, which is a dead device on QEMU virt
and most ARM64 SBCs — so init output disappeared and we only saw kernel panic
messages (which use earlycon, bypassing the console preference).

Also drop `quiet` from the default boot entry while we stabilise — we need the
kernel + init output visible right now.

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

build/grub/grub-arm64.cfg

@@ -51,25 +51,32 @@ else
 fi
 
 # --- ARM64 console string ---
-# Covers QEMU virt (ttyAMA0), Ampere/RPi-equivalent PL011 (ttyAMA0), and
-# Graviton/16550-compat (ttyS0). Last `console=` becomes the system console.
+# Order matters: the LAST `console=` is the primary system console (where /dev/console
+# points and where init's stdout/stderr land). Earlier `console=` entries get mirrored
+# kernel output but don't carry process I/O.
+#
+# Covers Graviton/16550 (ttyS0) as secondary and QEMU virt / PL011 / Ampere (ttyAMA0)
+# as primary. ttyAMA0 must be last for `-nographic` QEMU + most ARM64 SBCs.
+#
+# `quiet` is intentionally omitted from the default entry while we stabilise the
+# generic ARM64 boot path. Add back once boots are reliable.
 
 menuentry "KubeSolo OS (${slot_label})" {
     echo "Booting KubeSolo OS from ${slot_label}..."
     echo "Boot counter: ${boot_counter}, Boot success: ${boot_success}"
-    linux /vmlinuz kubesolo.data=LABEL=KSOLODATA console=ttyAMA0,115200 console=ttyS0,115200 quiet
+    linux /vmlinuz kubesolo.data=LABEL=KSOLODATA console=ttyS0,115200 console=ttyAMA0,115200
     initrd /kubesolo-os.gz
 }
 
 menuentry "KubeSolo OS (${slot_label}) — Debug Mode" {
     echo "Booting KubeSolo OS (debug) from ${slot_label}..."
-    linux /vmlinuz kubesolo.data=LABEL=KSOLODATA kubesolo.debug console=ttyAMA0,115200 console=ttyS0,115200
+    linux /vmlinuz kubesolo.data=LABEL=KSOLODATA kubesolo.debug console=ttyS0,115200 console=ttyAMA0,115200
     initrd /kubesolo-os.gz
 }
 
 menuentry "KubeSolo OS — Emergency Shell" {
     echo "Booting to emergency shell..."
-    linux /vmlinuz kubesolo.shell console=ttyAMA0,115200 console=ttyS0,115200
+    linux /vmlinuz kubesolo.shell console=ttyS0,115200 console=ttyAMA0,115200
     initrd /kubesolo-os.gz
 }
 
@@ -81,6 +88,6 @@ menuentry "KubeSolo OS — Boot Other Slot" {
         set root='(hd0,gpt2)'
         echo "Booting from System A (passive)..."
     fi
-    linux /vmlinuz kubesolo.data=LABEL=KSOLODATA kubesolo.debug console=ttyAMA0,115200 console=ttyS0,115200
+    linux /vmlinuz kubesolo.data=LABEL=KSOLODATA kubesolo.debug console=ttyS0,115200 console=ttyAMA0,115200
     initrd /kubesolo-os.gz
 }