fix: Add directory checks and optimize token usage

- Added check to skip directories when reading file content.
- Optimized token usage by removing unnecessary `\r` characters.

extensions/intellij/src/main/kotlin/com/github/continuedev/continueintellijextension/continue/IntelliJIde.kt

@@ -262,14 +262,16 @@ class IntelliJIDE(
                 content
             } else {
                 val file = File(URI(filepath))
-                if (!file.exists()) return ""
+                if (!file.exists() || file.isDirectory) return ""
                 withContext(Dispatchers.IO) {
                     FileInputStream(file).use { fis ->
                         val sizeToRead = minOf(100000, file.length()).toInt()
                         val buffer = ByteArray(sizeToRead)
                         val bytesRead = fis.read(buffer, 0, sizeToRead)
                         if (bytesRead <= 0) return@use ""
                         String(buffer, 0, bytesRead, Charset.forName("UTF-8"))
+                            // `\r` takes up unnecessary tokens
+                            .lineSequence().joinToString("\n")
                     }
                 }
             }