Fixes#1023.
## Problem
In Windows host mode, a single stalled delete syscall (AV/EDR filter driver, unresponsive mount, dying disk) wedged the job forever at `Cleaning up container`. `HostEnvironment.Remove()` bounds every teardown phase (`terminateRunningProcesses`, both `removePathWithRetry` calls) except the `CleanUp` callback — an unbounded `os.RemoveAll(miscpath)` assigned in `startHostEnvironment`. The runner then held its capacity slot indefinitely, the task was reaped as a zombie, and there were no diagnostics.
## Fix
- **Bound the cleanup (availability):** `Remove()` now runs `CleanUp` under `hostCleanupTimeout` (30s) via `runWithTimeout`; on timeout it logs a warning and continues job completion. The stuck goroutine is left to finish (a delete syscall can't be interrupted). Added debug logs around the phase.
- **Reclaim the leak (disk hygiene):** a timed-out cleanup can leave a scratch dir behind, so the existing idle stale-dir sweep is extended to also remove orphaned host-mode scratch dirs (16-hex names) under `Host.WorkdirParent`, leaving the shared `tool_cache` and operator data untouched. The `bind_workdir` gate is dropped from `shouldRunIdleCleanup` so host-mode runners run the sweep.
Reviewed-on: https://gitea.com/gitea/runner/pulls/1024
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
- Add idle-time cleanup for stale bind-workdir task directories instead of cleaning them on the task execution path.
- Make cleanup behavior configurable with `runner.startup_cleanup_age` as the stale-age threshold (default: `24h`) and `runner.idle_cleanup_interval` as the idle cleanup cadence (default: `10m`).
- Restrict cleanup scope to numeric task directory names only, to avoid touching operator-managed folders.
- Document the cleanup settings in `config.example.yaml` and `README.md`.
- Add tests for stale-directory cleanup, idle cleanup throttling, and config default/override parsing.
## Why
When a runner or host crashes, normal per-task cleanup may not run, leaving stale task directories under the bind-workdir root. Running this cleanup only while the runner is idle recovers that disk space without adding overhead to active job execution.
If you want, I can also tighten the wording around `startup_cleanup_age`, since the key name now reads a bit misleadingly relative to the actual behavior.
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Co-authored-by: silverwind <me@silverwind.io>
Reviewed-on: https://gitea.com/gitea/runner/pulls/870
Reviewed-by: silverwind <2021+silverwind@noreply.gitea.com>