age-home: Use curly-brackets for XDG_RUNTIME_DIR

[Kreyren]

To avoid having to do https://github.com/colonelpanic8/dotfiles/blob/4fd99eae63ef0ea8e6f23ac5e152352cb0fc1bf0/nixos/secrets.nix#L25C9-L29C116 while using agenix in user services.

Relevant discussion in NixOS chat: https://matrix.to/#/!RRerllqmbATpmbJgCn:nixos.org/$y_A0dX6Kj0TFTCCxQIXIK9VgqwzPXjBoZLCGbzmUxBA?via=nixos.org&via=matrix.org&via=tchncs.de

Heads-up: @colonelpanic8

[colonelpanic8]

@Kreyren thanks for the heads up. how did you find my configuration though? seems very random

[Kreyren]

@Kreyren thanks for the heads up. how did you find my configuration though? seems very random -- @colonelpanic8 (#280 (comment))

I was fixing a tagged code in NiXium, because it annoyed me that my web browser is barely usable without my PAC declaration and searching for language:nix systemd.user.services lists your configuration as 5th on my end:

which also had solution to my problem with agenix, but i don't want to make my nix code more complex than it has to be thus trying to fix it upstream instead (i like to have a coding ethique of never letting a code to force me into it's solution when i have designed another one that looks and works much better to force it instead).

In general doing the github search is my usual practice to find references on how something could be implemented and if i discover an issue then i like to submit merge requests to fix them e.g. heywoodlh/nixos-configs#11 (comment)