Add backtick string literals and formatter support

lyng-idea/src/main/kotlin/net/sergeych/lyng/idea/docs/LyngDocumentationProvider.kt

@@ -310,7 +310,7 @@ class LyngDocumentationProvider : AbstractDocumentationProvider() {
                 // Try literal and call-based receiver inference around the dot
                 val i = TextCtx.prevNonWs(text, dotPos - 1)
                 val className: String? = when {
-                    i >= 0 && text[i] == '"' -> "String"
+                    i >= 0 && (text[i] == '"' || text[i] == '`') -> "String"
                     i >= 0 && text[i] == ']' -> "List"
                     i >= 0 && text[i] == '}' -> "Dict"
                     i >= 0 && text[i] == ')' -> {

lyng-idea/src/main/kotlin/net/sergeych/lyng/idea/format/LyngPreFormatProcessor.kt

@@ -24,6 +24,7 @@ import com.intellij.psi.codeStyle.CodeStyleManager
 import com.intellij.psi.impl.source.codeStyle.PreFormatProcessor
 import net.sergeych.lyng.format.LyngFormatConfig
 import net.sergeych.lyng.format.LyngFormatter
+import net.sergeych.lyng.format.LyngStringDelimiterPolicy
 import net.sergeych.lyng.idea.LyngLanguage
 
 /**
@@ -170,6 +171,7 @@ class LyngPreFormatProcessor : PreFormatProcessor {
                 continuationIndentSize = options.CONTINUATION_INDENT_SIZE.coerceAtLeast(options.INDENT_SIZE.coerceAtLeast(1)),
                 applySpacing = true,
                 applyWrapping = false,
+                stringDelimiterPolicy = LyngStringDelimiterPolicy.PreferFewerEscapes,
             )
             val r = if (runFullFileIndent) currentLocalRange() else workingRangeLocal.intersection(currentLocalRange()) ?: currentLocalRange()
             val text = doc.getText(r)
@@ -189,6 +191,7 @@ class LyngPreFormatProcessor : PreFormatProcessor {
                 continuationIndentSize = options.CONTINUATION_INDENT_SIZE.coerceAtLeast(options.INDENT_SIZE.coerceAtLeast(1)),
                 applySpacing = settings.enableSpacing,
                 applyWrapping = true,
+                stringDelimiterPolicy = LyngStringDelimiterPolicy.PreferFewerEscapes,
             )
             val r = if (runFullFileIndent) currentLocalRange() else workingRangeLocal.intersection(currentLocalRange()) ?: currentLocalRange()
             val text = doc.getText(r)

lyng-idea/src/main/kotlin/net/sergeych/lyng/idea/highlight/LyngLexer.kt

@@ -101,8 +101,8 @@ class LyngLexer : LexerBase() {
             return
         }
 
-        // String "..." or '...' with simple escape handling
-        if (ch == '"' || ch == '\'') {
+        // String "...", `...`, or '...' with simple escape handling
+        if (ch == '"' || ch == '\'' || ch == '`') {
             val quote = ch
             i++
             while (i < endOffset) {