feat: boot mode parsing, FSBL-first flow, UI reorder

1. Boot mode parsing:
   - BootInfo.boot_mode field added
   - Matches 'Boot mode is JTAG', 'Boot Mode: QSPI', etc.
   - Fixed false version match: 'Boot mode is' no longer
     captures 'mode' as a version string

2. UART window cleanup:
   - Parsed boot info (mode/IP/ver) now only goes to main log
   - Raw serial lines still appear in UART window

3. Step 3 FSBL enforcement:
   - BIT step: after fpga -file, CPU is immediately halted (stop)
     to prevent Flash code from enabling MMU
   - ELF step: always dow FSBL → con → stop → dow bootloader

4. UI reorder:
   - FSBL ELF selector moved BEFORE Bootloader BIT
   - New layout: FSBL → BIT → ELF → Bootloader BIN → Flash → FW BIN
   - Fixed grid overlap (FSBL and Flash were both at row 6)

src/serial_monitor.py

@@ -23,6 +23,7 @@ class BootInfo:
     ip_address: str = ""
     version: str = ""
     boot_message: str = ""
+    boot_mode: str = ""
     raw_lines: list[str] | None = None
 
 
@@ -73,7 +74,7 @@ def parse_boot_output(lines: list[str]) -> BootInfo:
     ip_pattern = re.compile(r"\b(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})\b")
     version_patterns = [
         re.compile(r"[Vv]ersion[:\s]+([^\s;,\n]+)", re.IGNORECASE),
-        re.compile(r"[Bb]oot\s+([^\s;,\n]+)", re.IGNORECASE),
+        re.compile(r"[Bb]oot\s+(?:version\s+)?([Vv]?\d+\.\d+[^\s;,\n]*)", re.IGNORECASE),
         re.compile(r"[Ff]irm[Ww]are:?\s*([^\s;,\n]+)", re.IGNORECASE),
         re.compile(r"(?:^|[\s:=])([Vv]\d+\.\d+\.\d+[^\s;,\n]*)", re.IGNORECASE),
     ]
@@ -84,6 +85,10 @@ def parse_boot_output(lines: list[str]) -> BootInfo:
         re.compile(r"Linux\s+booted", re.IGNORECASE),
         re.compile(r"QSYS\s+ready", re.IGNORECASE),
     ]
+    boot_mode_patterns = [
+        re.compile(r"[Bb]oot\s*[Mm]ode\s*(?:is)?\s*[:\[=\s]*(\w+)"),
+        re.compile(r"BootMode\s*[:\[=\s]*(\w+)", re.IGNORECASE),
+    ]
 
     for line in lines:
         # Extract IP address
@@ -107,6 +112,14 @@ def parse_boot_output(lines: list[str]) -> BootInfo:
                     info.boot_message = line.strip()
                     break
 
+        # Extract boot mode
+        if not info.boot_mode:
+            for pattern in boot_mode_patterns:
+                match = pattern.search(line)
+                if match:
+                    info.boot_mode = match.group(1)
+                    break
+
     return info