Fixes cache initialization failures on unencrypted repositories and
standardizes environment variable configuration across all backup jobs.
Changes:
- Add BORG_UNKNOWN_UNENCRYPTED_REPO_ACCESS_IS_OK to unencrypted repos
  (fuchsia/viridian onsite) to bypass interactive confirmation prompt
- Refactor all environment.BORG_RSH to multiline attribute set format
  for consistency and future extensibility
The cache initialization error occurred after removing persistent timers
(commit 
		
	
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| .. | ||
| amdgpu-clocks | ||
| borgbackup | ||
| flatpak | ||
| libinput | ||
| pipewire | ||
| printing | ||
| snapper | ||
| ssh | ||
| udev | ||
| xserver | ||
| default.nix | ||