Stabilize daemon release tests

[glittercowboy]

Summary

Stabilizes release-sensitive daemon tests that rely on fake Pi subprocess timing.

Behavior

• Fake control subprocesses read stdin before emitting response frames so RunControl writes against a live reader.
• The duplicate-task loop test waits for task completion through the relay sink instead of relying on a fixed sleep.

Validation

• go test ./internal/pi -count=20
• go test ./internal/loop -run TestHandleTaskIgnoresDuplicateTaskID -count=10
• go test ./...
• go build -o /tmp/gsd-cloud-release-test-fix .
• git diff --check

Release Context

The daemon/v0.3.73 release workflow failed in TestRunControlParsesNullStatsContextUsage with a broken pipe while writing the control command. This PR removes that fake-process race before a replacement release tag is cut.

Summary by CodeRabbit

• Tests
  • Improved test stability by replacing long fixed sleeps with deterministic completion checks to reliably detect and assert single task completions.
  • Stabilized subprocess-based tests by ensuring fake subprocesses consume stdin, preventing premature progression and flakiness.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: 2093e714-a078-4959-993d-ca6991653f46

📥 Commits

Reviewing files that changed from the base of the PR and between 30a8fc1 and fd4f76a.

📒 Files selected for processing (1)

• internal/loop/daemon_test.go

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📝 Walkthrough

Walkthrough

This PR improves test reliability with two independent changes: a polling-based helper for task completion assertions in the loop daemon test, and stdin-consumption adjustments in four pi control tests to ensure subprocess stdin is drained before output is emitted.

Changes

Task Completion Polling Helper

Layer / File(s)	Summary
Polling Helper Definition internal/loop/daemon_test.go	Adds waitForTaskCompletes method to loopFakeRelay to poll for TaskComplete frames matching a task ID with a configurable count threshold and timeout.
Helper Usage internal/loop/daemon_test.go	Duplicate-task test now uses waitForTaskCompletes for explicit completion assertion instead of fixed sleep, attempting a 1-count wait then a 2-count wait (expected to time out) and asserting a single completion remains.

Subprocess Stdin Consumption

Layer / File(s)	Summary
Stdin-Consuming Scripts internal/pi/control_test.go	Four RunControl tests (TestRunControlExcludesUnrelatedHostSecrets, TestRunControlDoesNotUseStatsTokenAccountingAsContextUsage, TestRunControlParsesNullStatsContextUsage, TestRunControlRequiresTerminalResultFrame) now drain stdin via cat >/dev/null before subprocess output generation.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

Poem

A rabbit hops through test-time flows,
With helpers to poll where waiting goes,
And stdin drains like morning dew,
Test scripts now consume what's due. 🐰✨

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title 'Stabilize daemon release tests' directly corresponds to the main objective: stabilizing release-sensitive daemon tests that were failing due to timing issues.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch codex/pi-rust-release-test-fix

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@internal/loop/daemon_test.go`:
- Around line 1189-1193: Replace the unconditional time.Sleep with a bounded
negative wait to deterministically assert no second completion: after the
successful waitForTaskCompletes(t, 6*time.Second, "dup-task-1", 1) call, remove
the Sleep and call relaySink.waitForTaskCompletes(t, 1500*time.Millisecond,
"dup-task-1", 2) (or a similar short timeout) and assert it returns false, so
the test fails if a delayed duplicate completion appears instead of relying on
wall-clock sleep.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: f1c0bd94-73fe-4f1c-bb33-29ba2a3d201c

📥 Commits

Reviewing files that changed from the base of the PR and between 8cf8951 and 30a8fc1.

📒 Files selected for processing (2)

• internal/loop/daemon_test.go
• internal/pi/control_test.go