bugfix: disallow font size of 0

Dependencies

• [2] KKMFQDR4 editing source code from within the app
• [3] 2L5MEZV3 experiment: new edit namespace
• [4] KMSL74GA support selections in the source editor
• [5] QCPXQ2E3 add state arg to a few functions
• [6] OI4FPFIN support drawings in the source editor
• [7] LF7BWEG4 group all editor globals
• [8] H6QZ7GRR more precise name
• [9] LNUHQOGH start passing in Editor_state explicitly
• [10] XW7ANEJX switch shortcuts for bifold text

Change contents

• replacement in source_edit.lua at line 408
  [2.160545]→[2.160545:160630](∅→∅)
  − edit.update_font_settings(State, State.font_height-2)

  − Text.redraw_all(State)
  [2.160545]

  [2.160630]
  + if State.font_height > 2 then

  + edit.update_font_settings(State, State.font_height-2)

  + Text.redraw_all(State)

  + end
• replacement in edit.lua at line 371
  [3.12086]→[3.74:132](∅→∅),[3.132]→[3.6815:6842](∅→∅),[3.7857]→[3.6815:6842](∅→∅)
  − edit.update_font_settings(State, State.font_height-2)

  − Text.redraw_all(State)
  [3.12086]

  [3.12152]
  + if State.font_height > 2 then

  + edit.update_font_settings(State, State.font_height-2)

  + Text.redraw_all(State)

  + end