refactor(functions): standardize documentation, metadata, and wrappers

- Add comprehensive `--description` flags to all fish functions for better `help` and `functions` output.
- Introduce and correct `--wraps` flags to ensure proper completions for aliased commands (e.g., `top` wrapping `btop`, `zellij`, `upgrade` wrapping `paru`).
- Prepend descriptive comments before function definitions for better source readability.
- Add standard copyright and SPDX license identifiers to shell scripts.
- Enhance script robustness by ensuring consistent terminal checks (Kitty, WezTerm) and graceful fallbacks in window/tab spawning functions (`spwin`, `tab`).
- Implement graceful fallbacks to basic core utilities when preferred modern alternatives are missing (e.g., `top` falling back to system `top` if `btop` is missing, `view` falling back to `less` or `cat` if `nvim` is unavailable).
- Improve overall code consistency across the `functions/` directory.

functions/qr.fish

@@ -1,10 +1,20 @@
 # Copyright (C) 2026 Rootiest
 # SPDX-License-Identifier: AGPL-3.0-or-later
 
-function qr -d "Generate a QR code from text or pipe"
-    if set -q argv[1]
-        echo $argv | qrencode -t utf8
+# Generate a QR code from text or pipe
+function qr --description 'Generate a QR code from text or pipe'
+    if type -q qrencode
+        if set -q argv[1]
+            echo $argv | qrencode -t utf8
+        else
+            cat | qrencode -t utf8
+        end
     else
-        cat | qrencode -t utf8
+        if set -q argv[1]
+            curl -s "qrenco.de/$argv"
+        else
+            set -l input (cat)
+            curl -s "qrenco.de/$input"
+        end
     end
 end