fix(sheets): respect --plain flag for TSV output in metadata command

[mahsumaktas]

Summary

Fix sheets metadata --plain to output real tab-delimited values instead of space-padded columns. Also fixes a type mismatch build error in contacts_crud.go.

Problem

The sheets metadata command used tabwriter.NewWriter directly instead of the tableWriter(ctx) helper. The helper already checks outfmt.IsPlain(ctx) and bypasses tabwriter when --plain is set — but metadata was not using it.

This caused --plain output to have space-padded columns instead of real \t delimiters, breaking piping to tools like cut, awk, or csvtool that expect TSV.

# Before (spaces, not tabs):
ID   TITLE    ROWS  COLS
1    Sheet1   10    5

# After (real tabs):
ID⟶TITLE⟶ROWS⟶COLS
1⟶Sheet1⟶10⟶5

Changes

File	Change
internal/cmd/sheets.go	Replace direct tabwriter.NewWriter with tableWriter(ctx) in SheetsMetadataCmd; remove unused text/tabwriter import
internal/cmd/contacts_crud.go	Fix type mismatch: add explicit string type to given and org parameters in helper functions
internal/cmd/sheets_plain_test.go	Add 2 tests verifying tab delimiters in --plain mode for both sheets get and sheets metadata

Testing

go test ./internal/cmd/ -run "TestSheets" -v
# All 11 tests pass (9 existing + 2 new)

Related Issues

• Fixes sheets get --plain outputs spaces instead of tabs #209 — sheets get --plain outputs spaces instead of tabs
• Fixes Type Mismatch Errors in internal/cmd/contacts_crud.go #285 — Type mismatch errors in contacts_crud.go

[steipete]

Landed via temp rebase onto main.

• Gate: make ci
• Land commit: 057cbc7
• Merge commit: b6c5c79

Thanks @mahsumaktas!