refactor: ✨ (#418)

* refactor: ✨ move in one commit

Eveything in modules should probably be changed to `exported` defs.
The idea is to move everything first to keep proper history.

* refactor: 📝 add modules readme (wip)

* refactor: ✨ small move

* refactor: 📝 changed nestring, updated modules readme

* refactor: 📝 to document or not to document

* fix: 🐛 themes

replaced the template to use `main` and regenerated them
from lemnos themes.

* Revert "fix: 🐛 themes"

This reverts commit 4918d3633c8d2d81950a0ed0cfd9eb84241bc886.

* refactor: ✨ introduce sourced

- Created a source `root` in which sourcable demos are stored.
  Some might get converted to modules later on.
- Moved some files to bin too.

* fix: 🐛 fehbg.nu

* fix: 🐛 modules/after.nu

* moved some other stuff around

---------

Co-authored-by: Darren Schroeder <343840+fdncred@users.noreply.github.com>

sourced/progress_bar/progress_bar.nu

@@ -0,0 +1,52 @@
+# progress bar attempt
+# https://askubuntu.com/questions/747143/create-a-progress-bar-in-bash
+# https://www.shellscript.sh/tips/progressbar/
+
+# There is a strange artifact drawing the first two full blocks
+# You can see this artifact better in progress_bar_no_back.nu
+# I'm not sure what's going on nor how to fix it.
+
+let pb_len = 25
+let bg_fill = "▒"  # Fill up to $pb_len
+let blocks = ["▏" "▎" "▍" "▌" "▋" "▊" "▉" "█"]
+
+# "█" #8/8
+# "▉" #7/8
+# "▊" #3/4
+# "▋" #5/8
+# "▌" #1/2
+# "▍" #3/8
+# "▎" #1/4
+# "▏" #1/8
+
+# Turn off the cursor
+ansi cursor_off
+# Move cursor all the way to the left
+print -n $"(ansi -e '1000D')"
+# Draw the background for the progress bar
+print -n ($bg_fill | fill -c $bg_fill -w $pb_len -a r)
+
+1..<$pb_len | each { |cur_progress|
+    # This is kind of a hack because it's not incrementally drawing a new box
+    # It's drawing the entire row every time with a different padding amount
+    # echo $blocks.7 | fill --character $blocks.7 --width $it --align right
+
+    0..7 | each { |tick|
+        let cur_idx = ($tick mod 8)
+        let cur_block = (echo $blocks | get $cur_idx)
+        print -n $"(ansi -e '1000D')($cur_block | fill -c $blocks.7 -w $cur_progress -a r)"
+        sleep 20ms
+    }
+    print -n $"(ansi -e '1000D')"
+}
+# Fill in the last background block
+print $"($blocks.7 | fill -c $blocks.7 -w $pb_len -a r)"
+"Done"
+ansi cursor_on
+
+
+# Try to do this in the next version
+# Make it a custom command so you can do
+# set-progress 33 100
+# and the display look like
+# 33% (33/100) [███████████                    ]