fix(native): wait for the KDE feedback test listener

[juliusmarminge]

What changed

Register the feedback test bridge with Builder::serve_at before building its D-Bus connection. zbus waits for the method-call listener during this build, so the first authorization call cannot race listener startup. Keep the existing authorization checks and five-second deadline.

Why

The Rust job on main failed in only_kwin_can_read_commands_or_acknowledge_feedback even though the latest commit only changed web files. Registering the object on an already-running connection starts the listener asynchronously; the first Next call can arrive before its subscription exists and time out instead of returning AccessDenied.

Verification

Before, the unchanged crate reproduced the exact CI failure on iteration 13 when running four test processes on four CPU cores with Rust 1.98.1:

thread 'feedback::tests::only_kwin_can_read_commands_or_acknowledge_feedback' panicked at src/feedback.rs:249:9:
InputOutput(Custom { kind: TimedOut, error: "timed out" })
test result: FAILED. 10 passed; 1 failed

After, cargo test --locked --manifest-path native/kde-snap-shot/Cargo.toml passes all 11 tests. All 2,000 full-crate runs passed under the same contention, with zero failures. The PR Rust CI job also passes. Rust formatting and git diff --check pass.

Screenshots do not apply to this test-only change.

Checklist

• Small and focused
• Explained the change and cause
• Included before/after test evidence

Model: GPT-6. Harness: Codex.

Summary by CodeRabbit

• Tests
  • Improved authorization-flow test reliability by validating request handling through an active client connection.
  • Strengthened verification that authorization requests are processed and cleaned up correctly after testing.

[macroscopeapp]

Approvability

Verdict: Approved at 4b7c501

Macroscope's review found this PR approvable — This is a focused test-only fix that synchronizes D-Bus listener setup and changes no production code or customer-facing behavior. Its runtime impact is limited to making the existing KDE feedback test more reliable.

^{You can add or adjust custom eligibility rules. Learn more.}

[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

ℹ️ The exact PR base did not have a successful artifact. Baseline uses the latest successful main measurement shown below.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.5 KiB	13.6 KiB	+18 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	7.0 KiB	7.0 KiB	+2 B (+0.0%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.5 KiB	6.5 KiB	+16 B (+0.2%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	57.0 KiB	57.0 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	8	8	0 (0.0%)	21	✅
Claude	Total thread wire	13.6 KiB	13.6 KiB	+10 B (+0.1%)	15.1 KiB	✅
Claude	Thread snapshot wire	7.0 KiB	7.0 KiB	−4 B (−0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.5 KiB	6.5 KiB	+14 B (+0.2%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	57.8 KiB	57.8 KiB	0 B (0.0%)	66.4 KiB	✅
Claude	Live turn messages	9	9	0 (0.0%)	21	✅

Baseline: 299404a · PR result: 4b7c501 · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

• Codex decoded thread snapshot: 113.9 KiB
• Claude decoded thread snapshot: 114.6 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Team

Run ID: c411de20-fbe5-4fb3-a21a-3d2aa94a6cb1

📥 Commits

Reviewing files that changed from the base of the PR and between 8588d7f and 4b7c501.

📒 Files selected for processing (1)

• native/kde-snap-shot/src/feedback.rs

Included review availability: 9 reviews are currently available. Your included PR review attempts over the past 7 days set your current allowance at 10 reviews per hour.

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📝 Walkthrough

Walkthrough

The authorization test now uses a dedicated zbus connection that registers Bridge before requests and removes it during cleanup.

Changes

Authorization Test

Layer / File(s)	Summary
Dedicated Bridge connection native/kde-snap-shot/src/feedback.rs	The test registers Bridge during construction of a dedicated zbus connection, uses that connection for proxy calls, and removes Bridge from the same connection.

Estimated code review effort: 2 (Simple) | ~10 minutes

Merge Risk: ⚪ Minimal · up to 4b7c5

The authorization test now registers its feedback bridge before sending requests, removing the timing race that caused intermittent timeouts. The change is ready to merge with no remaining material risk identified.

Suggested reviewers: bil0000

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 1 functions across 1 files.
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.
Title check	✅ Passed	The title clearly identifies the main change: fixing the KDE feedback test listener race.
Description check	✅ Passed	The description explains what changed, why the race occurred, how it was verified, and why UI evidence does not apply. It is focused and includes a completed checklist.

✨ 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 t3code/investigate-flaky-rust-ci

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