fix(mount): stop repeated stalled bootstrap checkpoints

[miyaontherelay]

Fixes #360.\n\nAdds a persisted bootstrap checkpoint stall guard (default 20, configurable with RELAYFILE_BOOTSTRAP_STALL_CYCLES), surfaces a typed hard failure, and stops the mount polling runner when that failure recurs.\n\nCoverage includes partial unversioned tree checkpoints, persistence/reset behavior, delete safety, normal retry behavior, and the timer-path runner exit.\n\nValidation: go test ./... -count=1; go vet ./...; git diff --check.

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Review details

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: f7abf5b7-a067-4afa-a4a1-4e3c03203055

📥 Commits

Reviewing files that changed from the base of the PR and between ddf5c95 and d8a23d8.

📒 Files selected for processing (2)

• internal/mountsync/bootstrap_test.go
• internal/mountsync/syncer.go

📝 Walkthrough

Walkthrough

The mount syncer now tracks unchanged bootstrap checkpoints, raises a typed error at a configurable stall limit, persists terminal state, and resets counters when progress or completion occurs. Polling mounts terminate on this error while continuing to suppress ordinary cycle failures.

Changes

Bootstrap stall guard

Layer / File(s)	Summary
Stall configuration and error contracts internal/mountsync/syncer.go	Adds configurable stall limits, persisted counters, BootstrapStalledError, and dedicated status classification.
Checkpoint stall detection and state resets internal/mountsync/syncer.go, internal/mountsync/*_test.go	Compares bootstrap checkpoints, records stall cycles, persists terminal failures, resets state on progress or mode transitions, and tests resolution and reset behavior.
Polling termination and behavioral coverage cmd/relayfile-mount/*, internal/mountsync/tombstones_test.go	Propagates bootstrap stall errors from initial and scheduled reconciles while preserving nonfatal handling for ordinary failures, with polling and revision-gate tests.

Estimated code review effort: 4 (Complex) | ~45 minutes

Sequence Diagram(s)

sequenceDiagram
  participant PollingMount
  participant Syncer
  participant RemoteServer
  participant StateFile
  PollingMount->>Syncer: run reconcile
  Syncer->>RemoteServer: pull bootstrap page
  RemoteServer-->>Syncer: page or failure
  Syncer->>StateFile: compare and persist checkpoint
  StateFile-->>Syncer: stall count
  Syncer-->>PollingMount: continue or BootstrapStalledError
  PollingMount-->>PollingMount: terminate on typed error

Loading

Possibly related PRs

• AgentWorkforce/relayfile#263: Both changes update persisted bootstrap state and write-only-to-mirror transition handling.

Suggested reviewers: khaliqgant, kjgbot

Poem

I’m a rabbit guarding the tree,
Counting stalled hops patiently.
When the cursor will not move,
I thump and stop the polling groove.
Progress resets my little chart—
Then springtime syncs can safely start.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Linked Issues check	⚠️ Warning	The PR adds a stall guard and hard stop, but the linked issue also calls for empty-revision convergence and write-only mounts skipping remote reconciliation.	Add handling for empty or absent observed revisions as a valid initial revision and ensure write-only mounts do not reconcile the remote tree.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title is concise and accurately describes the main change: stopping repeated stalled bootstrap checkpoints.
Description check	✅ Passed	The description matches the implemented bootstrap stall guard, hard failure, and polling-runner exit behavior.
Out of Scope Changes check	✅ Passed	The changes stay within the bootstrap-stall fix and its related test coverage, with no clear unrelated features.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/bootstrap-empty-revision-360

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[github-actions]

Relayfile Eval Review

Run: .relayfile/evals/runs/2026-07-18T20-55-06-908Z-HEAD-provider
Mode: provider
Git SHA: 4964808

Passed: 4 | Needs human: 0 | Reviewable: 0 | Missing output: 0 | Failed: 0 | Skipped: 0

Human Review Cases

No reviewable human-review cases captured Relayfile output.

[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/mountsync/syncer.go`:
- Around line 4582-4587: Update recordBootstrapCycle to leave
BootstrapStallCycles unchanged when cause is or wraps context.Canceled and there
is no checkpoint advancement, while preserving the existing reset behavior and
continuing to count context.DeadlineExceeded and other errors.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

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

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 46d83347-ad0b-4598-a13e-fc5e061c70bf

📥 Commits

Reviewing files that changed from the base of the PR and between a030c75 and ddf5c95.

📒 Files selected for processing (6)

• cmd/relayfile-mount/main.go
• cmd/relayfile-mount/main_test.go
• internal/mountsync/bootstrap_test.go
• internal/mountsync/syncer.go
• internal/mountsync/syncer_test.go
• internal/mountsync/tombstones_test.go