A community based topic aggregation platform built on atproto

chore: update docs and references for lexicon migration master

Updates remaining documentation, code references, and configuration to reflect the lexicon namespace migration and labels changes. Changes: - Update docs (PRDs, CLAUDE.md) with new namespace references - Update API routes and handlers for community.post - Update aggregator client references - Update feed system documentation - Remove deprecated interaction/comment schemas (moved to feed/comment) No functional changes - documentation and reference updates only.