mkdist: redist runtime DLLs + versioned tester README

The first zips (pre-mkdist) shipped d3dx9_43.dll / msvcp140.dll /
vcruntime140.dll next to the exe -- testers without the VC++ / DirectX
redistributables cannot load the exe otherwise.  mkdist missed them (the
clean-extract boot test passed only because this machine has them system-
wide).  Carried into redist/ (recovered from BT411_4.11.341.zip) and
packaged next to the exe.

Also: players/README.txt -- the tester instructions (updated for the
unified build: one exe, clickable cockpit surround, trigger-config regroup,
the settled keymap, play_steam.bat) -- stamped with the version and placed
at the zip root, matching the original zips' shape.

Clean-extract verified on BT411_4.11.435.zip: root has README + 4 bats,
exe dir carries all 4 DLLs, glass-profile boot simulates.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

players/README.txt

@@ -0,0 +1,38 @@
+BattleTech {VERSION} -- multiplayer client
+==========================================
+
+IMPORTANT: FULLY EXTRACT this zip first (right-click - Extract All).
+Do NOT run anything from inside the zip.  The .bat files must sit next
+to the 'content' and 'build' folders.
+
+TO JOIN AN INTERNET GAME:   double-click  join.bat
+   (waits for the operator's session if it's not up yet)
+TO JOIN A LAN GAME:         double-click  join_lan.bat  (operator's LAN)
+SINGLE-PLAYER PRACTICE:     double-click  play_solo.bat  (no network)
+STEAM INTERNET PLAY:        double-click  play_steam.bat  (EXPERIMENTAL --
+   needs the Steam client running; host or join from the menu)
+
+Your seat and mech are assigned automatically by the operator.
+If the game closes unexpectedly, send the operator content\join.log.
+
+You start INSIDE the cockpit with the pod's MFD panels composited
+around the view (one window).  The red MFD buttons, radar rails and
+joystick buttons are all MOUSE-CLICKABLE -- right-click a button to
+latch it held.  Press V any time to toggle the external camera.
+
+CONTROLS (keyboard):
+  W/S or Up/Down ....... throttle lever        X / NumPad5 ... all stop
+  A/D or Left/Right .... turn pedals           Alt ........... reverse thrust
+  Q/E .................. torso twist           R/F ........... torso aim
+  NumPad 8/2/4/6 ....... torso aim/twist (alt) Shift ......... throttle up
+  1 or Space ........... main trigger          2 ............. middle thumb
+  3 or Ctrl ............ upper thumb (missiles) 4 ............ pinky
+  V view | B look-behind | M control mode | N schematic | J/K/L MFD pages
+  G (hold) + fire key .. regroup a weapon onto that trigger -- or hold a
+     weapon panel's red PROGRAM button with the mouse and tap a fire key;
+     the joystick diagram on the panel shows the binding live.
+
+An Xbox controller works out of the box.  Rebind keys in
+content\bindings.txt (regenerates with defaults if deleted).
+
+This build: {VERSION}.  Private -- do not redistribute.

tools/mkdist.py

@@ -66,8 +66,20 @@ def main():
             if f.lower().endswith(".dll"):
                 exes.append(d + "/" + f)
 
+    # System runtime DLLs the exe needs on a bare tester machine (32-bit
+    # d3dx9 + MSVC runtimes -- carried in redist/, shipped next to the exe;
+    # the first zips included them and machines without the redists fail
+    # to load the exe otherwise).
+    redist = ["redist/" + f for f in sorted(os.listdir("redist"))
+              if f.lower().endswith(".dll")] if os.path.isdir("redist") else []
+
     total = 0
     with zipfile.ZipFile(zpath, "w", zipfile.ZIP_DEFLATED, compresslevel=6) as z:
+        # versioned tester README at the zip root
+        if os.path.exists("players/README.txt"):
+            readme = open("players/README.txt", encoding="utf-8").read()
+            readme = readme.replace("{VERSION}", name.replace("BT411_", ""))
+            z.writestr(name + "/README.txt", readme)
         for p in bats:                       # bats at the zip ROOT (next to
             arc = os.path.basename(p)        # content\ + build\, per the guard)
             z.write(p, name + "/" + arc)
@@ -75,6 +87,9 @@ def main():
         for p in exes:
             z.write(p, name + "/" + p)
             total += os.path.getsize(p)
+        for p in redist:                     # next to the exe
+            z.write(p, name + "/build/Release/" + os.path.basename(p))
+            total += os.path.getsize(p)
         for p in tracked:
             if not os.path.exists(p):
                 print("  (skipping tracked-but-absent: %s)" % p)