Skip non-interactive live updates

[tobiasraabe]

Summary

Skip incremental live rendering when output is non-interactive, while keeping the live manager lifecycle intact.

Concretely:

• wire LiveExecution and LiveCollection with render_immediately=console.is_interactive
• skip per-event _update_table() / status refreshes when output is not interactive
• keep final build table rendering and live manager startup/shutdown behavior unchanged

Motivation

On non-interactive output, the incremental Rich redraws are not user-visible, but pytask still pays the formatting and refresh cost on every task event. This change keeps the same end result while avoiding that repeated work.

Validation

• uv run --group test pytest tests/test_live.py tests/test_build.py tests/test_execute.py tests/test_collect.py

Benchmark

Synthetic workload: 300 tiny non-provisional tasks, each with 3 path dependencies and 2 Annotated[..., Product] outputs.

On current main vs this branch:

• collect: 0.915s -> 0.921s (+0.6%, noise)
• build --force: 3.312s -> 2.893s (-12.7%)
• warm build: 1.507s -> 1.462s (-3.0%)

These runs were measured sequentially with hyperfine over 7 runs.