Migrate docdump tool from sts2-re

Queries the game's shipped sts2.xml (19,635 documented members) to
answer C# API questions without decompiling.

utils/docdump.py

@@ -0,0 +1,63 @@
+#!/usr/bin/env python3
+"""Dump .NET XML doc members (with summaries) for a namespace prefix."""
+import sys, re, xml.etree.ElementTree as ET
+
+XML = ("/Users/rasyidanakbar/Library/Application Support/Steam/steamapps/common/"
+       "Slay the Spire 2/SlayTheSpire2.app/Contents/Resources/"
+       "data_sts2_macos_arm64/sts2.xml")
+
+def clean(el):
+    if el is None: return ""
+    txt = "".join(el.itertext())
+    return re.sub(r"\s+", " ", txt).strip()
+
+def main():
+    prefix = sys.argv[1] if len(sys.argv) > 1 else ""
+    show_docs = "--docs" in sys.argv
+    types_only = "--types" in sys.argv
+    members_only = "--members" in sys.argv
+
+    tree = ET.parse(XML)
+    root = tree.getroot()
+    members = root.find("members")
+    if members is None:
+        print("no members"); return
+
+    types, mem = {}, []
+    for m in members.findall("member"):
+        name = m.get("name", "")
+        body = name[2:] if len(name) > 1 else name
+        kind = name[0]
+        if not body.startswith(prefix) and prefix:
+            continue
+        if kind == "T":
+            types[body] = m
+        elif kind in ("M", "P", "F"):
+            mem.append((body, m))
+
+    if not members_only:
+        for tname in sorted(types):
+            m = types[tname]
+            if types_only:
+                print("T: " + tname)
+            else:
+                print("=" * 78)
+                print("TYPE " + tname)
+                s = clean(m.find("summary"))
+                if s: print("  summary: " + s)
+                for tag in ("remarks", "example"):
+                    v = clean(m.find(tag))
+                    if v: print(f"  {tag}: {v}")
+    if not types_only:
+        for body, m in sorted(mem):
+            s = clean(m.find("summary"))
+            params = [(p.get("name"), clean(p)) for p in m.findall("param")]
+            ret = clean(m.find("returns"))
+            print("-" * 78)
+            print(body)
+            if s: print("   " + s)
+            for pn, pd in params:
+                print(f"   param {pn}: {pd}")
+            if ret: print("   returns: " + ret)
+
+main()