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/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}")