Auto merge of #12605 - metajack:win-app-fixes, r=larsbergstrom

Fix font metrics and switch to windows subsystem

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Currently fonts are using incorrect metrics and the app uses the console
subsystem. This patch adds aliases so that font metrics are found and
instructs the linker to use the windows subsystem.

NOTE: This is not yet ready to merge. The RUSTFLAGS isn't getting set right.

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