fix: handle escaped backslash sequences in quote parsing

Fixed the escape detection logic in joinQuotedLines() to properly count
consecutive backslashes. A quote is only escaped if preceded by an odd
number of backslashes:
- \\" = escaped backslash + closing quote (string ends)
- \\\" = escaped backslash + escaped quote (string continues)

Added test cases to verify the fix.

src/shared/__tests__/parse-command.spec.ts

@@ -77,6 +77,20 @@ describe("joinQuotedLines", () => {
 		const input = 'bd create "desc\nmore" && npm install\necho done'
 		expect(joinQuotedLines(input)).toEqual(['bd create "desc\nmore" && npm install', "echo done"])
 	})
+
+	it('should handle escaped backslash before closing quote (\\\\" sequence)', () => {
+		// \\" means escaped backslash (\\) followed by closing quote (")
+		// The string should end at the quote, not continue
+		const input = 'echo "hello\\\\"\necho done'
+		expect(joinQuotedLines(input)).toEqual(['echo "hello\\\\"', "echo done"])
+	})
+
+	it('should handle escaped backslash followed by escaped quote (\\\\\\" sequence)', () => {
+		// \\\" means escaped backslash (\\) followed by escaped quote (\")
+		// The string should continue past the quote
+		const input = 'echo "hello\\\\\\"world"\necho done'
+		expect(joinQuotedLines(input)).toEqual(['echo "hello\\\\\\"world"', "echo done"])
+	})
 })
 
 describe("parseCommand", () => {

src/shared/parse-command.ts

@@ -31,10 +31,20 @@ export function joinQuotedLines(command: string): string[] {
 
 	while (i < command.length) {
 		const char = command[i]
-		const prevChar = i > 0 ? command[i - 1] : ""
 
 		// Handle escape sequences (only in double quotes, single quotes are literal)
-		const isEscaped = prevChar === "\\" && inDoubleQuote
+		// Count consecutive backslashes before the current character
+		// If odd count, the current character is escaped; if even, it's not
+		// e.g., \" = escaped quote, \\" = escaped backslash + closing quote
+		let backslashCount = 0
+		if (inDoubleQuote) {
+			let j = i - 1
+			while (j >= 0 && command[j] === "\\") {
+				backslashCount++
+				j--
+			}
+		}
+		const isEscaped = backslashCount % 2 === 1
 
 		// Handle quote state changes
 		if (char === '"' && !inSingleQuote && !isEscaped) {