feat(tasks): add uploading task status

[shark0F0497]

Pull Request Checklist

Please ensure your PR meets the following requirements:

• 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 an explicit uploading task state to the recorder/transfer flow and improves task recovery observability when upload triggering or completion is retried.

It also standardizes recorder/transfer logs with device/task context, updates production dashboard task statistics, and refreshes design documentation for the callback-driven task lifecycle.

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Motivation

• Finished recordings were moving directly toward completion semantics without a durable intermediate state for "waiting for upload".
• When upload_request could not be sent because Transfer was disconnected or timed out, operators had limited visibility into why a task remained unfinished.
• Duplicate upload_complete events needed to remain ACK-safe without re-triggering batch/order advancement.
• Existing logs repeated task IDs inside messages and were hard to scan during recording, auto-dispatch, cancel, and upload flows.

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Changes

Modified Files

• internal/api/handlers/task.go - Marks finished recordings as uploading, records upload request send errors, clears upload errors after successful send, and logs state transitions with device/task prefixes.
• internal/api/handlers/transfer.go - Completes tasks after verified upload ACK, keeps duplicate completed ACKs idempotent, logs completed transitions, and clears upload request errors after manual upload requests succeed.
• internal/api/handlers/axon_rpc.go - Standardizes recorder state/config logs with [RECORDER][device][task] style context.
• internal/api/handlers/production_dashboard.go - Includes uploading in dashboard task counts and trends.
• internal/api/handlers/task_state_recovery_test.go - Adds coverage for finish callback upload timeout/disconnected recovery behavior.
• internal/api/handlers/recorder_axon_interaction_test.go - Updates recorder interaction coverage for the uploading lifecycle.
• internal/api/handlers/transfer_connection_takeover_test.go - Updates Transfer disconnect/takeover expectations for uploading tasks.
• internal/api/handlers/batch.go - Removes a stale task status trigger map left over from the removed task update API.
• internal/storage/database/migrations/000001_initial_schema.up.sql - Updates the initial task status enum definition for fresh installs.
• docs/designs/production-units.md - Documents uploading, verified ACK completion, and duplicate ACK behavior.
• docs/designs/task-manage.md - Refreshes the task state machine to match recorder callbacks and Transfer upload events.
• docs/designs/upload-service-design.md - Aligns upload flow documentation with the new task state.

Added Files

• internal/api/handlers/task_uploading.go - Adds shared helpers for owned task uploading/failed/error-message transitions.
• internal/storage/database/migrations/000005_task_uploading_status.up.sql - Adds uploading to the persisted task status enum.
• internal/storage/database/migrations/000005_task_uploading_status.down.sql - Provides rollback from uploading to in_progress before removing the enum value.
• docs/designs/task-uploading-status.zh.html - Adds the UT/design validation document for the uploading status flow.

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 for API clients. Existing pre-upload task states remain accepted on upload completion for weak-network recovery, while the normal post-recording path now uses uploading.

Database migration adds the new uploading enum value and includes a rollback path that rewrites uploading tasks to in_progress before removing the enum value.

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Testing

Test Environment

• Local Keystone branch: feat/task-uploading-status
• Go test cache redirected to /tmp/go-build to avoid read-only home cache issues

Test Cases

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

Commands run:

env GOCACHE=/tmp/go-build go test -run 'TestRecordingFinish|TestTaskHandlerAxonTransferWriteTimeout' ./internal/api/handlers/... -v
env GOCACHE=/tmp/go-build go test ./internal/api/handlers/...
env GOCACHE=/tmp/go-build GOLANGCI_LINT_CACHE=/tmp/golangci-lint golangci-lint run

Manual Testing Steps

• Verified a recording finish flow where Keystone transitions the task to uploading and triggers Transfer upload.
• Verified auto-dispatch of the next task after finish/upload trigger.
• Verified cancel/clear behavior after the next task config is applied.
• Reviewed Keystone Edge logs for structured [RECORDER][device][task] and [TRANSFER][device][task] messages.

Test Coverage

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

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Screenshots / Recordings

N/A. Backend flow and documentation change.

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Performance Impact

• Memory usage: No change
• CPU usage: No change
• Throughput: No change
• Lock contention: No change

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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

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Related Issues

• N/A

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Additional Notes

• Duplicate upload_complete remains safe: Keystone still sends upload_ack, but does not re-run batch/order advancement for tasks that were already completed.
• upload_request send failures keep the task in uploading and write tasks.error_message for operator visibility instead of marking the task failed.

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Reviewers

N/A

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Notes for Reviewers

• Please review the upload lifecycle around OnRecordingFinish, onUploadComplete, and upload_failed handling.
• Please verify the migration rollback semantics for active uploading tasks.
• Please review the log wording for readability during recorder/transfer troubleshooting.

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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)