PowerToys Command Palette: Polyphonic Pinyin mismatch – "重启计算机" only found with "zhongqi", not "chongqi"

### Microsoft PowerToys version

0.100.2

### Installation method

GitHub

### Area(s) with issue?

Command Palette

### Steps to reproduce

1. Ensure the system language is set to Chinese (Simplified).
2. Activate PowerToys Command Palette.
3. Type the correct Pinyin `chongqi` (which corresponds to the Chinese word "重启", meaning "restart") in the search box.
4. Observe the search results.

### ✔️ Expected Behavior

The command **重启计算机** (from the "Windows 系统命令" / Windows System Commands extension) should appear in the results when typing `chongqi`. The character "重" in "重启" is pronounced `chong`, and the Pinyin search should match all valid pronunciations of a polyphonic character.

### ❌ Actual Behavior

Only typing `zhongqi` returns the expected results. Searching with the correct Pinyin `chongqi` yields no match for "重启"-related commands. This suggests the Pinyin index does not account for polyphonic characters, using only one pronunciation per character rather than all valid pronunciations.

### Upload Bug Report ZIP-file

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### Additional Information

_No response_

### Other Software

_No response_

Start in the PowerToys Command Palette search and indexing path, then trace how the Windows System Commands extension supplies the 重启计算机 entry. Reproduce the search with zhongqi and chongqi under Simplified Chinese, and confirm that the completed change matches all valid pronunciations without breaking existing results.

Written by the indexing model from the issue text.