Sync sheet pins should honor currently selected hierarchical sheet

Description

Currently, the workflow for syncing sheet pins is massively slowed down compared to what it was before:

• Press "Sync sheet pins"
• Find the correct sheet in the tabs (which is very slow if they don't fit into the width of the dialog
• Click on it
• Actually do the syncing

Assuming I have already selected a hierarchical sheet in the editor, the corresponding tab could automatically be selected in the "Sync sheet pins" dialog. Then, the first 3 steps above could be skipped.

KiCad Version

Application: KiCad Schematic Editor x64 on x64

Version: 9.0.6, release build

Libraries:
	wxWidgets 3.2.8
	FreeType 2.13.3
	HarfBuzz 10.2.0
	FontConfig 2.15.0
	libcurl/8.13.0-DEV Schannel zlib/1.3.1

Platform: Windows 11 (build 26100), 64-bit edition, 64 bit, Little endian, wxMSW

Build Info:
	Date: Oct 30 2025 19:36:12
	wxWidgets: 3.2.8 (wchar_t,wx containers)
	Boost: 1.88.0
	OCC: 7.9.1
	Curl: 8.13.0-DEV
	ngspice: 45.2
	Compiler: Visual C++ 1944 without C++ ABI
	KICAD_IPC_API=ON

Locale: 
	Lang: en_US
	Enc: UTF-8
	Num: 1,234.5
	Encoded кΩ丈: D0BACEA9E4B888 (sys), D0BACEA9E4B888 (utf8)