feat: add MySQL parser to monorepo (#30)

This commit adds the MySQL parser from the standalone mysql-parser repository into the unified parser monorepo.

Changes:
- Added MySQL grammar files (MySQLLexer.g4, MySQLParser.g4)
- Added helper files (builtin_functions.go, keywords.go, mysql_base_lexer.go)
- Added predefined.tokens file for lexer
- Added test infrastructure with 24 example SQL files
- Created Makefile for building and testing the parser
- Updated package names from 'parser' to 'mysql'
- Updated import paths to github.com/bytebase/parser/mysql
- Updated CI workflow to include mysql in the test matrix
- Generated parser files using ANTLR 4 with Go target
- All 24 tests passing successfully

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude <[email protected]>

Author: h3n4l

.github/workflows/tests.yml

@@ -34,7 +34,7 @@ jobs:
         id: set-matrix
         run: |
           # List of all available parsers
-          ALL_PARSERS="redshift postgresql cql snowflake tsql doris trino plsql googlesql"
+          ALL_PARSERS="redshift postgresql cql snowflake tsql doris trino plsql googlesql mysql"
           # Add more parsers here as they are added to the repository
           # ALL_PARSERS="redshift mysql postgresql"
 

mysql/Makefile

@@ -0,0 +1,7 @@
+all: build test
+
+build:
+	antlr -Dlanguage=Go -package mysql -visitor -o . MySQLLexer.g4 MySQLParser.g4
+
+test:
+	go test -v -run TestMySQLDBSQLParser