Tweaks to mounted kitchen and workshop (#82883)

* Tweaks to mounted kitchen and workshop

Add WORKBENCH flag, to crafting can be done on those. They're flat
surfaces after all. Workbench specs are similar to simple table, so a
dedicated workbench (like we found on some specialized trucks) still
make sense.

Add CABLE_PORTS flag, so we can connect and recharge tools. Yes, now you
can recharge your smartphone while in bed on the default RV. The ports
make senses as you can "attach" tools to similar effect. The systems
were made concurrently and do not account for each other, the reason
that may have escaped from earlier audit.

* Update data/json/vehicleparts/modular_tools.json

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

---------

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

Author: andrewhr

data/json/vehicleparts/modular_tools.json

@@ -97,7 +97,8 @@
     "damage_reduction": { "all": 30 },
     "durability": 80,
     "size": "50 L",
-    "flags": [ "CARGO", "OBSTACLE", "FLAT_SURF", "VEH_TOOLS" ],
+    "flags": [ "CARGO", "OBSTACLE", "FLAT_SURF", "WORKBENCH", "CABLE_PORTS", "VEH_TOOLS" ],
+    "workbench": { "multiplier": 1.1, "mass": "150 kg", "volume": "20 L" },
     "//": "allow tools common for both kitchen unit and workshop; unpowered or low-power and no fume hood required",
     "allowed_tools": [
       "aluminum_pan",