Fixed a few bugs.

Additional events and rewards have been provided for Trebizond players when choosing to declare war on the Ottomans proactively.

Added new religious mission trees for the Pontic path, including Zoroastrian, Christian, and Muslim branches, along with several building-related missions.

Provide some modifiers for Casual mode.

Optimized the icon for the Pontic government mechanic.

Updated the descriptions for some missions and reward modifiers related to Trebizond, thanks to the contribution from Magnetic Rod.

Added new difficulty settings: Casual, Standard, and Challenge modes.

Introduced a general disaster: Purple Chamber Strife, as well as the starting disaster Lost Lamb for Standard and Challenge difficulties.

Fixed and optimized several minor issues.

Optimized the condition descriptions for the "Integrate Theme" diplomatic action.

Fix a few bugs.