feat: implement multi-stage candidate ingestion and matching pipeline with UI tracking and backend schema support

feat: slider max dynamically set from CSV row count (header excluded)

fix: use real candidate count, remove stage2 cap, add full error logging

fix(ui): add navbar link to API Docs alongside system reset

fix: cross-session JD leak, show match% not rank, pass all candidates through pipeline, fix growth_velocity always 60

fix: growth_velocity always 60% bug - handle JSON string and empty work_exp

feat: complete rewrite of UI/UX for streamlining and pruning

feat: implement automated ingestion pipeline with state persistence and add database maintenance utilities

refactor: unified session view, pipeline polling, db wipe

feat: updated pipeline to support matching against multiple JDs sequentially

feat: add pipeline page, session delete with Qdrant cleanup, explain worker, and final frontend polish