Adjust locale settings for local usage

.config/shell/locale

@@ -1,24 +1,42 @@
 #!/bin/sh
 
-# Locale settings for headless machines
+# Locale settings for desktop machines
+# as run by the author of this `dotfiles` repository
+
+# Requires the en_US.UTF-8, en_DK.UTF-8, en_IE.UTF-8, and de_DE.UTF-8
+# locales be installed which is checked by ~/.local/bin/ensure-locales
+
+# Other hosts (e.g., servers) usually lack some of these locales,
+# and Debian's /etc/ssh/ssh_config forwards all of them via `SendEnv LANG LC_*`
+# => ~/.local/bin/ssh, ~/.local/bin/scp, and ~/.local/bin/sftp
+#    send `LC_ALL=C.UTF-8` on top to mask them on remote hosts
 
 
-# Drop what a client may forward over `ssh`,
-# because `AcceptEnv LANG LC_*` may be set in /etc/ssh/sshd_config
-unset \
-    LC_ALL \
-    LC_ADDRESS \
-    LC_COLLATE \
-    LC_CTYPE LC_IDENTIFICATION \
-    LC_MEASUREMENT \
-    LC_MESSAGES \
-    LC_MONETARY \
-    LC_NAME \
-    LC_NUMERIC \
-    LC_PAPER \
-    LC_TELEPHONE \
-    LC_TIME
+export LANG=en_US.UTF-8               # Fallback for any (future) LC_* not set below
 
 
-# Set every LC_* category implicitly with the `$LANG` fallback
-export LANG=C.UTF-8
+# Base: US English for language, text handling, and sorting
+
+export LC_COLLATE=en_US.UTF-8         # Dictionary sort order => Ignore punctuation
+export LC_CTYPE=en_US.UTF-8           # UTF-8 character classification
+export LC_MESSAGES=en_US.UTF-8
+export LC_NUMERIC=en_US.UTF-8         # 1,234.56 rather than 1.234,56
+
+
+# Exceptions: European conventions with English number formatting
+
+export LC_MEASUREMENT=en_IE.UTF-8     # Use the metric system
+export LC_MONETARY=en_IE.UTF-8        # Euro with 1,234.56
+export LC_PAPER=en_IE.UTF-8           # Use DIN-A4 for a page
+export LC_TIME=en_DK.UTF-8            # ISO dates, 24h clock, Monday first
+
+
+# (German) metadata
+
+export LC_ADDRESS=de_DE.UTF-8         # German postal layout
+export LC_IDENTIFICATION=en_US.UTF-8
+export LC_NAME=en_US.UTF-8
+export LC_TELEPHONE=de_DE.UTF-8       # For "+49" and "030 12345"
+
+
+export TZ="Europe/Berlin"