perf: reuse PDF text extraction and streamline search normalization

fix: synchronize Reader v2 proxy contracts

feat: support additional Reader formats

fix: fallback missing bucket reader objects

Fix Reader source IDs and bound PDF opening reads

Use source IDs for Reader resolution

Complete Reader recovery and static asset updates

Add complete on-demand search for chapter books

Preserve reader source identity for shared assets

Track project test suites

chore: keep deployment repository lean

fix: harden reader asset delivery