docs: comprehensive 1.0 rewrite + fix(wrapper): Linear sync on exit

Docs refresh:
- README: fix tool count (26→25), test count (650→652), remove broken
  links, stale pricing tiers, version tags, MCP Quick Usage internals
- cli.md: full rewrite covering all command groups (~55→200 lines)
- Remove 9 stale docs (postgres, RALPH, BM25, changelog, etc.)
- Update status.md, roadmap.md, DEVELOPMENT.md, SETUP.md for v1.0.0

Linear sync fix:
- Add Linear sync to codex-sm, claude-sm, and pty-wrapper exit handlers
- Gated on LINEAR_API_KEY, 10s timeout, non-fatal catch

Author: StackMemory Bot (CLI)