feat(statistics): add operator data production stats

[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 data collector self-service data production statistics APIs and documents the operator personal production page design.

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Motivation

• Let data collectors view their own daily production metrics after logging in to Synapse.
• Reuse the existing admin data production statistics semantics while enforcing backend scoping to the current collector.

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Changes

Modified Files

• internal/api/handlers/data_production_statistics.go - Adds operator statistics routes and wraps existing summary/trend/breakdown logic with current-collector scoping.
• internal/api/handlers/data_production_statistics_test.go - Adds tests for ignoring request collector filters and overriding them with JWT claims.
• internal/server/server.go - Registers /operator/statistics/data-production routes for data_collector.

Added Files

• docs/designs/operator-data-production-statistics.zh.html - Documents final product/API decisions for operator personal production statistics.

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

Admin statistics APIs remain unchanged. Operator APIs are additive.

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Testing

Test Environment

Local development environment.

Test Cases

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

Manual Testing Steps

Not performed.

Test Coverage

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

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Screenshots / Recordings

Not applicable.

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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

• Fixes #
• Related to #
• Refers to #

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Additional Notes

The existing /production/dashboard backend API is retained because it is still used by the Synapse admin big-screen dashboard.

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Reviewers

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Notes for Reviewers

• Please review current-collector scoping in internal/api/handlers/data_production_statistics.go.
• Confirm that incoming collector_operator_id cannot be used to view another collector's statistics.

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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)