Add bulk QA progress SSE

[shark0F0497]

Pull Request Checklist

• Code follows the style guidelines
• Tests pass locally
• Code is formatted
• Documentation updated if needed
• Commit messages follow conventional commits
• PR description is complete and clear

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Summary

This PR adds a second built-in episode QA check for empty recordings and adds realtime bulk QA run progress over SSE for Data Ops bulk QA.

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Motivation

• Operators need QA to catch recordings that have a valid-looking MCAP file but no actual recorded messages/topics.
• Bulk QA currently runs asynchronously without a durable run snapshot or realtime progress, so the UI cannot tell when a submitted batch has finished without refreshing.

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Changes

Modified Files

• [internal/api/handlers/data_ops.go](internal/api/handlers/data_ops.go) - wires Data Ops bulk action dependencies and bulk run routes.
• [internal/api/handlers/data_ops_bulk.go](internal/api/handlers/data_ops_bulk.go) - changes bulk QA submission to create a tracked run and process episodes with progress accounting.
• [internal/api/handlers/data_ops_test.go](internal/api/handlers/data_ops_test.go) - adds coverage for bulk run creation, active-run conflict, progress counts, stale-run interruption, and SSE snapshots.
• [internal/server/server.go](internal/server/server.go) - interrupts stale queued/running bulk QA runs on service startup.
• [docs/designs/data-ops-bulk-actions-api.zh.html](docs/designs/data-ops-bulk-actions-api.zh.html) - documents the run snapshot and SSE progress design.

Added Files

• [internal/api/handlers/data_ops_bulk_run.go](internal/api/handlers/data_ops_bulk_run.go) - implements bulk QA run persistence, current-run lookup, run snapshot API, and SSE streaming.
• [internal/storage/database/migrations/000006_bulk_runs.up.sql](internal/storage/database/migrations/000006_bulk_runs.up.sql) - creates the bulk run table.
• [internal/storage/database/migrations/000006_bulk_runs.down.sql](internal/storage/database/migrations/000006_bulk_runs.down.sql) - drops the bulk run table.

Deleted Files

• None.

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Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update (documentation changes only)
• Refactoring (code improvement without functional changes)
• Performance improvement (code changes that improve performance)
• Test changes (adding, modifying, or removing tests)

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Impact Analysis

Breaking Changes

None.

Backward Compatibility

Fully backward compatible. Existing single-episode QA and bulk sync behavior remain unchanged. Bulk QA responses now include a run snapshot so clients can track progress.

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Testing

Test Environment

Local Go test environment with GOCACHE=/tmp/go-cache.

Test Cases

• Unit tests pass locally
• Integration tests pass locally
• E2E tests pass (if applicable)
• Manual testing completed

Commands run:

git diff --check
GOCACHE=/tmp/go-cache go test ./internal/api/handlers -run 'Test(ParseDataOps|DataOps|PreviewBulk|BulkRun|StreamBulkRun|InterruptActive|CurrentBulkRun|GetBulkRun)' -count=1 -v
GOCACHE=/tmp/go-cache go test -race ./internal/api/handlers -run 'Test(BulkRun|StreamBulkRun|InterruptActive|CurrentBulkRun|GetBulkRun)' -count=1
GOCACHE=/tmp/go-cache go test ./internal/server ./internal/storage/database -count=1
GOCACHE=/tmp/go-cache go test ./internal/api/handlers -count=1

Manual Testing Steps

Not performed in browser from this repo.

Test Coverage

• New tests added
• Existing tests updated
• Coverage maintained or improved

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Screenshots / Recordings

N/A.

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Performance Impact

• Memory usage: Slight increase while an active bulk QA run is tracked and streamed.
• CPU usage: No material change outside active bulk QA processing.
• Throughput: No material change.
• Lock contention: No material change expected.

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Documentation

• README.md updated
• ARCHITECTURE.md updated
• CONTRIBUTING.md updated
• API documentation updated
• Design docs updated in docs/designs/
• No documentation changes needed

Generated Swagger files were not refreshed locally because the local swag setup was unavailable.

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Related Issues

• None.

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Additional Notes

• Only bulk QA gets realtime progress in this PR. Bulk sync keeps the existing accepted/background behavior.
• The active run model is intentionally scoped to one global bulk_qa run at a time.

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Reviewers

N/A.

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Notes for Reviewers

• Please review [internal/api/handlers/data_ops_bulk_run.go](internal/api/handlers/data_ops_bulk_run.go) for run lifecycle, SSE streaming, and reconnect behavior.
• Please review the migration and startup interruption behavior for stale queued/running runs.

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Checklist for Reviewers

• Code changes are correct and well-implemented
• Tests are adequate and pass
• Documentation is updated and accurate
• No unintended side effects
• Performance impact is acceptable
• Backward compatibility maintained (if applicable)