fix(query): fix incorrect total_bytes_len in string view

[sundy-li]

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Summary

1. add more asserts
2. fix incorrect total_bytes_len in string view

using const UNKNOWN_LEN: u64 = u64::MAX to track with the total_bytes_len was a bad idea cause it may introduce overflow during add/sub.

closes #16880

Tests

• [ ] Unit Test
• [x] Logic Test
• [ ] Benchmark Test
• [ ] No Test - Explain why

Type of change

• [ ] Bug Fix (non-breaking change which fixes an issue)
• [ ] New Feature (non-breaking change which adds functionality)
• [ ] Breaking Change (fix or feature that could cause existing functionality not to work as expected)
• [ ] Documentation Update
• [x] Refactoring
• [ ] Performance Improvement
• [ ] Other (please describe):

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This change is