message: Document highlight features in the shell
diff: @@ -13587,6 +13587,11 @@ static const char *(azHelp[]) = {
  ".changes on|off Show number of rows changed by SQL",
  ".check GLOB Fail if output since .testcase does not match",
  ".clone NEWDB Clone data into NEWDB from the existing database",
  + ".constant ?COLOR? Sets the syntax highlighting color used for constant values",
  + " COLOR is one of:",
  + " red|green|yellow|blue|magenta|cyan|white|brightblack|brightred|brightgreen",
  + " brightyellow|brightblue|brightmagenta|brightcyan|brightwhite",
  + ".constantcode ?CODE? Sets the syntax highlighting terminal code used for constant values",
  ".databases List names and files of attached databases",
  ".dbconfig ?op? ?val? List or change sqlite3_db_config() options",
  ".dbinfo ?DB? Show status information about the database",
  @@ -13615,6 +13620,7 @@ static const char *(azHelp[]) = {
  ".fullschema ?--indent? Show schema and the content of sqlite_stat tables",
  ".headers on|off Turn display of headers on or off",
  ".help ?-all? ?PATTERN? Show help text for PATTERN",
  + ".highlight [on|off] Toggle syntax highlighting in the shell on/off",
  ".import FILE TABLE Import data from FILE into TABLE",
  " Options:",
  " --ascii Use \\037 and \\036 as column and row separators",
  @@ -13637,6 +13643,11 @@ static const char *(azHelp[]) = {
  #ifdef SQLITE_ENABLE_IOTRACE
  ".iotrace FILE Enable I/O diagnostic logging to FILE",
  #endif
  + ".keyword ?COLOR? Sets the syntax highlighting color used for keywords",
  + " COLOR is one of:",
  + " red|green|yellow|blue|magenta|cyan|white|brightblack|brightred|brightgreen",
  + " brightyellow|brightblue|brightmagenta|brightcyan|brightwhite",
  + ".keywordcode ?CODE? Sets the syntax highlighting terminal code used for keywords",
  ".limit ?LIMIT? ?VAL? Display or change the value of an SQLITE_LIMIT",
  ".lint OPTIONS Report potential schema issues.",
  " Options:",
  