OpenViST Rust task report — version 0.1.0, MIT

Tested with Rust 1.90.0, Edition 2024 on Linux. Standard library only.
Save these files together in a new practice folder:
  Cargo.toml.txt as Cargo.toml
  task_report.rs.txt as task_report.rs
  tasks.tsv.txt as tasks.tsv
  rust-project-LICENSE.txt as LICENSE

From that folder:
  cargo test --offline
  cargo run --offline --bin task-report -- tasks.tsv
The report on stdout is:
  records=3
  open=2
  closed=1
Cargo prints build/run messages on stderr. To see only program output, use:
  cargo run --quiet --offline --bin task-report -- tasks.tsv

Contract:
Exactly one ordinary local file argument. At most 65,536 bytes, strict UTF-8,
no BOM, LF line endings only, header status<TAB>title, 1..1,000 records.
Status is exactly open or closed. Title is 1..100 Unicode scalar values, with
no control characters. Spaces and Unicode line separators U+2028/U+2029 are
allowed in a title; this is a TSV counter, not a configuration-key validator.
Exactly one separating tab per record. Duplicate rows count separately.
One final LF is optional; other blank records are invalid. No quoted-field or
CSV rules. No network requests, file writes, Unicode normalization or secrets
redaction. Titles are never printed. Output appears only after full validation.
Input errors: empty stdout, 'error: invalid input' on stderr, exit 2.
Output write failure: exit 1. Successful report: exit 0.

The byte limit does not impose a time limit on opening/reading a file. Use
ordinary practice files, not devices, pipes or remote filesystems. The tool is
an educational example, not a sandbox or a production deployment guide.
Sixteen built-in tests cover the recorded cases; they do not prove exhaustive
correctness. Run tests again after changing source, limits, or dependencies.