feat: add inventory hero and upgrade widgets

[TckTcm]

Summary

This PR requires the C++ code to be merged first.

Adds Python-side inventory widgets and wrappers for native hero inventory selection and item upgrade flows.

This builds on the native C++ inventory upgrade support and exposes usable widgets for selecting hero inventories, applying armor upgrades, and applying weapon upgrades without mouse-click emulation.

Changes

• Added Hero Inventory Selector widget:

  • selects a hero in the inventory equipment panel through the native frame message flow
  • validates inventory frame/agent state before sending the selection request

• Added Inventory Armor Upgrader widget:

  • applies runes and insignias from inventory bags to equipped armor
  • supports player and party heroes as targets
  • resolves target inventory ID and equipped armor item through native wrappers
  • validates upgrade compatibility before sending the native upgrade request

• Added Inventory Weapon Upgrader widget:

  • applies weapon upgrades from inventory bags
  • supports weapons in bags and equipped weapons for player/heroes
  • classifies prefix, suffix, and inscription upgrade slots
  • validates upgrade compatibility before sending the native upgrade request

• Added Python wrappers for native inventory APIs:

  • GetInventoryIDFromAgent
  • IsInventoryIDValid
  • GetEquippedItemID
  • GetUpgradeSlot
  • ValidateUpgrade
  • ApplyUpgrade

• Added Python wrappers for inventory equipment panel helpers:

  • GetInventorySelectedAgentID
  • GetInventoryEquipmentFrameID

• Moved widget constants into enum source files:

  • armor equipment slots
  • armor upgrade slots
  • weapon upgrade slot mapping
  • inventory equipment frame constants

• Updated stubs for the new native bindings.