⚡ batch insert bib_chips in replace_bib_chips and replace_rd_data

[iwismer]

💡 What:
Optimized replace_bib_chips and replace_rd_data in services/receiver/src/db.rs by replacing single-row loop insertions with multi-row batch inserts in chunks of 50 items (insert_bib_chips_conn).

🎯 Why:
Previously, replace_bib_chips and replace_rd_data iterated over input bib->chip tuples and executed individual INSERT OR REPLACE statements per item, creating an N+1 SQLite execution bottleneck during bulk chip imports.

📊 Measured Improvement:
Measured via tests::benchmark_bulk_operations:

• replace_bib_chips (10,000 items): baseline ~62.4ms -> optimized ~23.1ms (~2.7x faster / 63% reduction in execution time)
• replace_rd_data (10,000 items each table): baseline ~115.1ms -> optimized ~80.3ms (~1.4x faster)

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PR created automatically by Jules for task 14249822904381087987 started by @iwismer

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