Fix action enum shift crash from upstream SET_TAB_TITLE

Upstream added GHOSTTY_ACTION_SET_TAB_TITLE at position 33, shifting
all subsequent enum values. Swift/Xcode couldn't import the new value,
causing every action after position 33 to be misinterpreted (e.g.
COMMAND_FINISHED matched as START_SEARCH, crashing on garbage pointer).

Fix: move SET_TAB_TITLE to the end of the C ABI enum so existing
values keep their positions. Handle it via raw value in Swift.

Author: lawrencecchen

Sources/GhosttyTerminalView.swift

@@ -2592,7 +2592,7 @@ class GhosttyApp {
                 }
             }
             return true
-        case ghostty_action_tag_e(rawValue: 33): // GHOSTTY_ACTION_SET_TAB_TITLE
+        case ghostty_action_tag_e(rawValue: 64): // GHOSTTY_ACTION_SET_TAB_TITLE (moved to end to avoid shifting existing values)
             let title = action.action.set_title.title
                 .flatMap { String(cString: $0) } ?? ""
             if let tabId = surfaceView.tabId,