Summary

Add a --header (-H) flag that optionally prints column names as the first output row, improving usability when piping output to another sql-pipe invocation or saving as a named CSV.

Changes

src/main.zig

• Added header: bool field to ParsedArgs
• Added --header / -H flag parsing in parseArgs
• Added writeField — RFC 4180 CSV field quoting (handles commas, quotes, newlines)
• Added printHeaderRow — writes column names from sqlite3_column_name as the first CSV row
• Modified execQuery to accept a header parameter and print the header before data rows
• Updated help text to document the new option

docs/sql-pipe.1.scd

• Added -H, --header option documentation
• Added examples showing --header usage and round-trip piping

Acceptance Criteria

• --header flag (or -H) prints column names as the first output row
• Header off by default (preserves current streaming behaviour)
• Header column names come from the SQLite column alias or original name
• When --header is set, the output is valid CSV that can be piped back into sql-pipe

Testing

# Default (no header) — unchanged behaviour
echo 'name,age\nAlice,30\nBob,25' | sql-pipe 'SELECT * FROM t'
# Alice,30
# Bob,25

# With --header
echo 'name,age\nAlice,30\nBob,25' | sql-pipe --header 'SELECT * FROM t'
# name,age
# Alice,30
# Bob,25

# With -H and SQL alias
echo 'name,age\nAlice,30\nBob,25' | sql-pipe -H 'SELECT name AS "full name", age FROM t'
# full name,age
# Alice,30
# Bob,25

# Round-trip piping
echo 'name,age\nAlice,30\nBob,25' | sql-pipe -H 'SELECT * FROM t' | sql-pipe 'SELECT name FROM t'
# Alice
# Bob

Closes #10