Manual character symbol setting on web demo

[Bedrovelsen]

Absolutely enjoying being able to play with chafa in a web browser after several thoughts about doing something to do so myself over last year or two but never getting beyond the fruitful thinking stage so firstly many thanks for doing so!

Just curious if support for manually setting symbols in the Symbols and Fill options is supported or could be easily supported if not so?

Such as:
FILL

ascii-‘@'-‘#’

OR

SYMBOL

[" ", ".", "·", "•", "-", "|", "/", "\\", "┌", "┐", "└", "┘", "┴", "┬", "┤", "├", "█", "▀", "▄", "▐", "▌", "▘", "▝", "▖", "▗", "┼", "⌓", "⌒", "⌐", "⌌", "<", ">", "^", "v", "▲", "▼", "◄", "►"]

Trying to remove certain characters from the ASCII symbol set that get picked to often for what ascii character used in placements when set to lowest colour options and ascii character set as seen for example below using the initial demo image. I can edge detect and edge thin and process the images before conversion of course to limit this issue but being able to `ascii-"@" would be handy when playing with the options on the web version before jumping into a local install of chafa later)

Colors: FGBG
Symbols: Ascii
Fill: None

                                                                                
                                                                                
                        ___yaggy_                                               
                    yg@@@@@@@@@@@@@g_                                           
                _yg@@@@@@@R@B$$@$@@@@@$                                         
              _a@@@@@@@M4@@P?~~@A@$RA@@-                                        
            yg@@@@@@$M@^  ~~,  f@@@@@@$y_yL_                                    
          y@@@@@@@~> ! `     .  f3~%@@@@@@@"`_                                  
        _g@@@@@@@@y               Q@@$@$@$0@@=-                                 
w_,.  yg@@@@@@@@@@@@g@ar`          ``R@=@@$@@                                   
  _yg@@@@@@@@0@@@@R$@@E_yg :          ~   5@M^                                 _
@@@@@@@@@$@@@M@Z@@@$@@$@$yyay-             7^                                yg@
@@@@@@@$; ~~9$@H$$``F7 7MB$F`\                                             y$@@@
@M@@P#@A$=- "@g@$@@$a@ ' `_~   _                                          a@@@@$
@G{~s  '~   4$P=~~$@$K`' ,'. ,~`                                        g$@@@$@\
@@am@$g  .  ~/     Ft   -_g@gy__~                                    _a@@@@$@$  
09$@@@@$5_'.  .       -%y@@@@@@@y                                 _=_a@@@@@F~=  
E@M$@@TDeQg@aw__  `  _y@@@@@@@@@@gy               y_            .;_a@@@P@\`   _y
@$  *?  =R2B@$$=9?@g$@@@@@@B@@@@@@@@$gy     .  _a@@@g_      __yg@@@@@F4^ _ya4@$@
@@y_.    _gggy$yg@@@@@@@@@@$@@@@@@@@@@@@y_   ~=R_ 4~~TF  *$P@@@@@P@TF5@g@P~y@@@@
@@@@@@@@@@@@@@@@@@@@$$a$$$@@@$@@$~$@@$[4EM@$ayyy___yygyya$R@44@yya$@@F~~_@@@@P~~
@@@$@@@@@@@@@@@@@@M@@@@@$@@@@@@ 4^_EE4g_~E 4y~4@@@@$$@$$@@@@@@@@@ZLLL_y@@FF-`` _
@@@@$@$a@@@@ 7@@@@@@@@@$$@@g@$@$ {"@__TM@y_  =.~?@@@M4@@@aZ~~Y=-  ._a@@@@@==YT~~
@@@~~t^i `F  yR@$@$$@$@@g$4M&@$@g   "%"Ggs%Z=w__  ~~4ay_~?=-`F=*gy$@@E____gz===r
@F   .'  ,r$F~?``~@@A$@@@$_ f`@4@$_   `=b=R$@y3$$@@gyyy__f_=_ya@@@~~~``````     
@           `    ` $@@F~$@~Ts.~ ~@@@g_   "~5@@@@$$@@@**gga$PF~~~`~~ _ggag$@@@@ga
P                 -4^~^a$yg@$ga_ '~=#@@$aayyy__yyyaa@@@@@@@@$aaa$@@@@@@@@@@@@@@@

Colors: FGBG
Symbols: None
Fill: Ascii

                                                                                
                                                                                
                        ___yaggy_                                               
                    yg@@@@@@@@@@@@@g_                                           
                _yg@@@@@@@R@B$$@$@@@@@$                                         
              _a@@@@@@@M4@@P?~~@A@$RA@@-                                        
            yg@@@@@@$M@^  ~~,  f@@@@@@$y_yL_                                    
          y@@@@@@@~> ! `     .  f3~%@@@@@@@"`_                                  
        _g@@@@@@@@y               Q@@$@$@$0@@=-                                 
w_,.  yg@@@@@@@@@@@@g@ar`          ``R@=@@$@@                                   
  _yg@@@@@@@@0@@@@R$@@E_yg :          ~   5@M^                                 _
@@@@@@@@@$@@@M@Z@@@$@@$@$yyay-             7^                                yg@
@@@@@@@$; ~~9$@H$$``F7 7MB$F`\                                             y$@@@
@M@@P#@A$=- "@g@$@@$a@ ' `_~   _                                          a@@@@$
@G{~s  '~   4$P=~~$@$K`' ,'. ,~`                                        g$@@@$@\
@@am@$g  .  ~/     Ft   -_g@gy__~                                    _a@@@@$@$  
09$@@@@$5_'.  .       -%y@@@@@@@y                                 _=_a@@@@@F~=  
E@M$@@TDeQg@aw__  `  _y@@@@@@@@@@gy               y_            .;_a@@@P@\`   _y
@$  *?  =R2B@$$=9?@g$@@@@@@B@@@@@@@@$gy     .  _a@@@g_      __yg@@@@@F4^ _ya4@$@
@@y_.    _gggy$yg@@@@@@@@@@$@@@@@@@@@@@@y_   ~=R_ 4~~TF  *$P@@@@@P@TF5@g@P~y@@@@
@@@@@@@@@@@@@@@@@@@@$$a$$$@@@$@@$~$@@$[4EM@$ayyy___yygyya$R@44@yya$@@F~~_@@@@P~~
@@@$@@@@@@@@@@@@@@M@@@@@$@@@@@@ 4^_EE4g_~E 4y~4@@@@$$@$$@@@@@@@@@ZLLL_y@@FF-`` _
@@@@$@$a@@@@ 7@@@@@@@@@$$@@g@$@$ {"@__TM@y_  =.~?@@@M4@@@aZ~~Y=-  ._a@@@@@==YT~~
@@@~~t^i `F  yR@$@$$@$@@g$4M&@$@g   "%"Ggs%Z=w__  ~~4ay_~?=-`F=*gy$@@E____gz===r
@F   .'  ,r$F~?``~@@A$@@@$_ f`@4@$_   `=b=R$@y3$$@@gyyy__f_=_ya@@@~~~``````     
@           `    ` $@@F~$@~Ts.~ ~@@@g_   "~5@@@@$$@@@**gga$PF~~~`~~ _ggag$@@@@ga
P                 -4^~^a$yg@$ga_ '~=#@@$aayyy__yyyaa@@@@@@@@$aaa$@@@@@@@@@@@@@@@

I could be confused and making up that the official chafa supports this as a option if so disregard this as its outside of the scope of this excellent chafa wasm variant!