v0.2.0 - Lower Bound, Range Queries & Flat Slice Benchmarks

What's Changed in v0.2.0

Full English Localization & Accessibility

• Complete English Translation: Translated the entire benchmark suite CLI outputs (src/main.rs), metrics summaries, and documentation from French to English for global readability, consistency, and standard open-source accessibility.

New Features & APIs

• Lower Bound Search (PgmIndex::lower_bound): Fast predecessor lookup returning the first key $\ge \text{target}$ with $O(\log S + \log \epsilon)$ complexity and partition-point fallback guarantee.
• Zero-Copy Range Queries (PgmIndex::range): Standard RangeBounds<u64> slice query returning sub-slices directly without allocations.

Statistical Benchmarks & Baselines

• Integrated standard slice::binary_search as an explicit baseline alongside BTreeMap in the 10-run 1,000,000-key benchmark suite (src/main.rs).
• Updated documentation with 3-way performance comparisons showing up to 4.45x faster lookups vs BTreeMap and 2.90x vs binary search on flat slices, while reducing index memory footprint by 99.97%.

Quality & Test Suite

• Comprehensive unit tests covering empty indices, single-element vectors, inverted/out-of-bounds ranges, and statistical partition_point parity across 1,000 queries.
• Clean cargo clippy, cargo fmt, and 100% green CI pipeline.

Documentation & Maintenance

• Archived v0.1.1 documentation into docs/history/README_v0.1.1.md.
• Added GitHub Sponsors / funding configuration (.github/FUNDING.yml).

Full Changelog: v0.1.1...v0.2.0

v0.1.1: Quality Audit & Expanded Test Coverage

Code Quality: Resolved clippy lints, formatted source.
Invariants: Added debug assertions for sorted non-decreasing order.
Test Suite: Added tests for duplicates, extreme limits, epsilon=1, memory accounting.
CI/CD: GitHub Actions workflow for PR verification.
Documentation: Added References & Resources section.