Fix three bugs in double right-click fishing mode

[dlamanna]

Summary

Fixes three bugs in doubleClick.lua that caused the double right-click fishing method to be unreliable:

• Overly aggressive UI frame blocking — the old check (GetMouseFoci()[1] ~= nil) blocked double-click whenever any UI frame was under the cursor, including non-interactive frames like textures and status bars. Now only blocks on interactive elements (Button, EditBox, CheckButton, Slider).
• Spurious third ActionHandler call — when the second click ended the watch manually, the pending PoolDelayer timer was still active and would fire Angleur_ActionHandler a third time after expiry. Now the timer is cancelled using a "doubleClickWatch" identifier.
• Erroneous MouselookStart/MouselookStop in GLOBAL_MOUSE_DOWN — during the watch state, mouse-down was toggling mouselook, which caused the camera to get stuck or interfere with double-click detection. Removed this block entirely.

Test plan

• Enable double right-click fishing method
• Verify double right-click casts fishing near water
• Verify clicking on UI buttons (bags, menus) is not intercepted
• Verify camera movement (right-click hold) still works normally
• Verify no stuck mouselook after double-clicking