Use hybrid CRT linkage instead of full static (microsoft#5913)

See https://aka.ms/hybridcrt for additional details.

When building ReleaseStatic, use the hybrid linkage model. This produces
a binary that is closer in size to the dynamic linkage than the full
static, relying on the UCRT binary that ships in Windows to provide the
core CRT functionality. As an example, the WindowsPackageManager.dll is
~90 KB larger as hybrid than dynamic, but is another ~160 KB larger as
static than hybrid.

Author: JohnMcPMS

.github/actions/spelling/expect.txt

@@ -124,6 +124,7 @@ DCPPREST
 debian
 decompressor
 dedupe
+defaultlib
 DEFT
 deigh
 deleteifnotneeded
@@ -228,6 +229,7 @@ Howto
 hre
 hresults
 hwnd
+hybridcrt
 Hyperlink
 IARP
 IAttachment
@@ -568,6 +570,7 @@ UCase
 ucasemap
 UChars
 ucnv
+ucrt
 udwgp
 uec
 ULONGLONG

src/Directory.Build.props

@@ -28,6 +28,17 @@
       <MultiProcessorCompilation>true</MultiProcessorCompilation>
     </ClCompile>
   </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)'=='ReleaseStatic'">
+    <Link>
+      <!-- Link statically against the runtime and STL, but link dynamically against the CRT by ignoring the static CRT
+           lib and instead linking against the Universal CRT DLL import library. This "hybrid" linking mechanism is
+           supported according to the CRT maintainer. Dynamic linking against the CRT makes the binaries a bit smaller
+           than they would otherwise be if the CRT, runtime, and STL were all statically linked in. 
+           See https://aka.ms/hybridcrt for more details. -->
+      <IgnoreSpecificDefaultLibraries>%(IgnoreSpecificDefaultLibraries);libucrt.lib</IgnoreSpecificDefaultLibraries>
+      <AdditionalOptions>%(AdditionalOptions) /defaultlib:ucrt.lib</AdditionalOptions>
+    </Link>
+  </ItemDefinitionGroup>
 
   <!-- For C# -->
   <PropertyGroup Condition="'$(WinGetMacros)' != ''">