feat(parser): implement semicolon-separated statements

Add support for semicolon-terminated statements according to the
updated grammar. This change enables executing multiple SQL statements
in a single input by separating them with semicolons. Key improvements
include:
- Update grammar to require semicolons after statements
- Add Semicolon token to the tokenizer
- Implement error recovery by skipping to next semicolon on parse errors
- Create helper functions for checking semicolons in statement parsers
- Add tests for multiple statements and error conditions

src/meta_commands.rs

@@ -1,6 +1,6 @@
 use crate::branding;
 
-#[derive(Debug, Eq, PartialEq)]
+#[derive(Debug, Eq, PartialEq, Clone)]
 pub enum MetaCommand {
     Exit,
     About,