feat: ScalableBloomFilter

[MovAh13h]

Adds ScalableBloomFilter — a bloom filter that grows automatically when its initial capacity is exceeded.

• Maintains a list of slices (plain BloomFilters), adding a new larger slice when the current one fills
• Each new slice is growth times larger in capacity and has a tighter FPR by a tightening ratio, keeping the total FPR bounded by the target
• Default parameters: growth = 2, tightening = 0.5
• Added BloomError::InvalidGrowthFactor and BloomError::InvalidTighteningRatio
• Added construction, no-false-negatives, auto-growth, behavioural, and statistical FPR tests
• Added to serde test suite via serde_tests!(scalable_bloom_filter, ScalableBloomFilter, no_with_params)
• Updated README filters table