Add segment coverage ledger and mid-project plan for Crusader decompilation

- Created `crusader_segment_coverage_ledger.csv` to track segment coverage status, types, and known functions.
- Introduced `plan-mid.md` as a mid-project tracker outlining progress, objectives, and implementation priorities for the decompilation effort.
- Added scripts in `pyghidra_plans` to assist with instruction window dumping and reference inspection for the object at `0x4588`.
- Implemented functionality to scan for instruction uses of specific targets related to the decompilation project.

pyghidra_plans/dump_instruction_windows.py

@@ -0,0 +1,76 @@
+TARGETS = [
+    "0004:5b8c",
+    "0004:5bbf",
+    "0004:5ea7",
+    "0004:6430",
+    "0009:92ad",
+    "0009:b1cd",
+    "000a:493e",
+    "000a:4a68",
+    "000a:b9e5",
+    "000a:ba66",
+    "000d:9d5e",
+    "000d:a3b7",
+]
+
+BEFORE_COUNT = 6
+AFTER_COUNT = 8
+
+
+listing = program.getListing()
+address_factory = program.getAddressFactory()
+
+
+def as_address(text):
+    segment_text, offset_text = text.split(":")
+    return address_factory.getAddress(f"{segment_text}:{offset_text}")
+
+
+def collect_window(center):
+    instructions = []
+
+    current = listing.getInstructionContaining(center)
+    if current is None:
+        current = listing.getInstructionAt(center)
+    if current is None:
+        current = listing.getInstructionBefore(center)
+        if current is not None and current.getNext() is not None and current.getNext().getAddress() <= center:
+            current = current.getNext()
+    if current is None:
+        return instructions
+
+    cursor = current
+    for _ in range(BEFORE_COUNT):
+        cursor = cursor.getPrevious()
+        if cursor is None:
+            break
+    if cursor is None:
+        cursor = current
+        while cursor.getPrevious() is not None and len(instructions) < BEFORE_COUNT:
+            cursor = cursor.getPrevious()
+
+    while cursor is not None:
+        instructions.append(cursor)
+        if cursor == current:
+            break
+        cursor = cursor.getNext()
+
+    cursor = current.getNext()
+    while cursor is not None and len(instructions) < BEFORE_COUNT + AFTER_COUNT + 1:
+        instructions.append(cursor)
+        cursor = cursor.getNext()
+
+    return instructions
+
+
+for target_text in TARGETS:
+    target = as_address(target_text)
+    print(f"=== {target} ===")
+    window = collect_window(target)
+    if not window:
+        print("<no instruction window>\n")
+        continue
+    for insn in window:
+        marker = "=>" if insn.getAddress() == target else "  "
+        print(f"{marker} {insn.getAddress()} {insn}")
+    print("")

pyghidra_plans/inspect_4588_refs.py

@@ -0,0 +1,34 @@
+from ghidra.program.model.symbol import RefType
+
+
+TARGETS = {0x4588, 0x458A}
+
+
+def format_addr(addr):
+    return addr.toString()
+
+
+listing = program.getListing()
+function_manager = program.getFunctionManager()
+reference_manager = program.getReferenceManager()
+
+seen = set()
+
+for target in TARGETS:
+    addr = program.getAddressFactory().getDefaultAddressSpace().getAddress(target)
+
+    print(f"TARGET {format_addr(addr)}")
+    refs = reference_manager.getReferencesTo(addr)
+    iterator = refs.iterator() if hasattr(refs, "iterator") else refs
+    for ref in iterator:
+        from_addr = ref.getFromAddress()
+        function = function_manager.getFunctionContaining(from_addr)
+        key = (str(from_addr), str(addr))
+        if key in seen:
+            continue
+        seen.add(key)
+        instruction = listing.getInstructionContaining(from_addr)
+        code_unit = listing.getCodeUnitContaining(from_addr)
+        text = instruction.toString() if instruction is not None else code_unit.toString()
+        function_name = function.getName() if function is not None else "<no function>"
+        print(f"  FROM {format_addr(from_addr)} {function_name} {ref.getReferenceType()} {text}")

pyghidra_plans/scan_4588_instruction_uses.py

@@ -0,0 +1,17 @@
+TARGET_HEX = ("4588", "458a")
+
+listing = program.getListing()
+function_manager = program.getFunctionManager()
+
+instruction = listing.getInstructions(True)
+
+while instruction.hasNext():
+    insn = instruction.next()
+    text = insn.toString().lower()
+    if not any(token in text for token in TARGET_HEX):
+        continue
+
+    address = insn.getAddress()
+    function = function_manager.getFunctionContaining(address)
+    function_name = function.getName() if function is not None else "<no function>"
+    print(f"{address} {function_name} {insn}")