# Sentence Length Statistics Implementation

* **Task ID:** sentence-length-statistics_78.stevejs
* **Reviewer:** stevejs
* **Area:** code
* **Motivation (WHY):**
  - Replace sentence count statistics with sentence length analysis for literary research
  - Provide character-based length distribution data for narrative analysis
  - Enable understanding of writing style patterns across different works and authors
  - Support literary computational analysis workflows
* **Acceptance Criteria:**
  1. Replace sentence count tracking with sentence length tracking (in characters)
  2. Update RunStats and FileStats to include length distribution metrics
  3. Provide histogram/distribution data in stats output (min, max, mean, median, percentiles)
  4. Update console output to show length statistics instead of count statistics
  5. Maintain performance characteristics while collecting length data
  6. Update help text and documentation to reflect length focus
* **Deliverables:**
  - Modified FileStats structure with sentence length metrics
  - Updated RunStats aggregation for length statistics
  - Histogram/distribution calculation logic
  - Updated console output formatting
  - Modified JSON stats output schema
  - Performance validation that length calculation doesn't impact throughput
* **References:**
  - Current sentence count implementation in parallel_processing module
  - RunStats structure in main.rs
  - Console output formatting for statistics display

## Pre-commit checklist:
- [ ] All deliverables implemented
- [ ] Tests passing (`cargo test`)
- [ ] Claims validated
- [ ] Documentation updated if needed
- [ ] **ZERO WARNINGS**: `./scripts/validate_warning_free.sh` passes completely