build: add a format target and one shared editor config

The Lua modules were split between tabs and spaces because nothing pinned a
style; .editorconfig is what lua-language-server reads on save, so the editor
and the tree now agree. clang-format already had a config and left native/
unchanged. Embedded modules regenerate from the reformatted ui.lua.

lua/test/hints.lua

@@ -1,25 +1,43 @@
 package.path = "./lua/lib/?.lua;" .. package.path
 
 local drawn = {}
-local roles = {"confirm", "back", "right"}
+local roles = { "confirm", "back", "right" }
 
 gui = {
   FONT_SMALL = 0,
   STYLE_NORMAL = 0,
-  color = function(r, g, b) return r * 65536 + g * 256 + b end,
-  getWidth = function() return 300 end,
-  getHeight = function() return 240 end,
-  getFontHeight = function() return 8 end,
-  getTextWidth = function(_, text) return #text * 6 end,
-  fillRect = function(x, y, w, h) drawn.strip = {x, y, w, h} end,
-  drawText = function(_, x, _, text) drawn[#drawn + 1] = {text = text, x = x} end,
+  color = function(r, g, b)
+    return r * 65536 + g * 256 + b
+  end,
+  getWidth = function()
+    return 300
+  end,
+  getHeight = function()
+    return 240
+  end,
+  getFontHeight = function()
+    return 8
+  end,
+  getTextWidth = function(_, text)
+    return #text * 6
+  end,
+  fillRect = function(x, y, w, h)
+    drawn.strip = { x, y, w, h }
+  end,
+  drawText = function(_, x, _, text)
+    drawn[#drawn + 1] = { text = text, x = x }
+  end,
 }
 
-input = {getButtons = function() return roles end}
+input = {
+  getButtons = function()
+    return roles
+  end,
+}
 
-local hints = require("hints")
+local hints = require "hints"
 
-local height = hints.draw({back = "Close", confirm = "Select", up = "Scroll"})
+local height = hints.draw { back = "Close", confirm = "Select", up = "Scroll" }
 assert(height == 14, "height covers the font plus padding")
 assert(drawn.strip[2] == 226, "the strip sits at the bottom by default")
 
@@ -30,7 +48,7 @@ assert(drawn[1].x == 60 and drawn[2].x == 207, "each label centres in its slot")
 
 drawn = {}
 roles = {}
-assert(hints.draw({confirm = "Select"}) == 14, "a device with no buttons still clears the strip")
+assert(hints.draw { confirm = "Select" } == 14, "a device with no buttons still clears the strip")
 assert(#drawn == 0 and drawn.strip, "nothing is labelled, but the strip is cleared")
 
-print("ok")
+print "ok"