cmdpal: use the unified Windows Terminal Versioning scheme (#39320)

This pull request adopts the unified versioning scheme used by Windows Terminal, Notepad, and hundreds of other internal and public projects that relied on "XES" or "PackageES".

It only does so for the command palette.

All command palette assets will be versioned according to the Major and Minor number in `src/modules/cmdpal/custom.props`. This includes DLLs, EXEs, NuGet packages and MSIX bundles.

This will ensure that all artifacts that we produce are versioned
properly:

| thing   | version (ex.)   |
|---------|-----------------|
| dll/exe | 0.2.2505.08001  |
| nupkg   | 0.2.250508001   |
| appx    | 0.2.3269.0      |

For reference, here's the version format:

### EXE, DLL, .NET Assembly

    0.2.2505.08001
    ^ ^  ^ ^  ^  ^
    | |  | |  |  `-Build # on that date
    | |  | |  `-Day
    | |  | `-Month
    | |  `-Year
    | `-Minor
    `-Major

### NuGet Package

    0.2.250508001
    ^ ^  ^ ^ ^  ^
    | |  | | |  `-Build # on that date
    | |  | | `-Day
    | |  | `-Month
    | |  `-Year
    | `-Minor
    `-Major

### AppX Package

    0.2.01281.0 (the leading 0 will be removed)
    ^ ^ ^  ^^ ^
    | | |  || `-Contractually always zero (a waste)
    | | |  |`-Build # on that date
    | | |  `-Number of days in [base year]
    | | `-Number of years since [base year]
    | `-Minor
    `-Major
    
    [base year] = $(XesBaseYearForStoreVersion)

It is expected that the base year is changed every time the version
number is changed.