feat/fix: Rich token usage popovers, robust LiteLLM context window bounds logic, and Skill management refactor

Refactor AI Config and Fix Login failure: Migrated services to a structured api directory, updated backend schemas for multiple TTS/STT providers, and improved settings/chat UI coverage.

refactor: consolidate chat into swarm_control everywhere

fix(sync): broadcast CLEANUP and PURGE instantly on session delete, update protobufs

refactor(frontend): move remaining pages into feature modules