Add flate2 and tar dependencies for archive extraction support in file
operations. Update documentation with:
- New BASIC keywords: SWITCH/CASE, WEBHOOK, INSTR, IS_NUMERIC
- HTTP operations: POST, PUT, PATCH, DELETE_HTTP, GRAPHQL, SOAP
- Data operations: SAVE, INSERT, UPDATE, DELETE, MERGE, FILTER, etc.
- File operations: READ, WRITE, COMPRESS, EXTRACT, GENERATE_PDF, etc.
Simplify README and add appendices for external services and environment
variables. Add monitoring dashboard and player UI docs.