OpenDream 0.3.21

Release v0.3.21.\n\n- Shortens the README for Hacker News launch traffic while moving detailed operator/contributor material into docs.\n- Adds visible alpha, integration-maturity, and fixture-eval caveats near the top of the README.\n- Adds issue templates for install problems, integration requests, memory failure cases, and real-world eval proposals.

v0.3.19

• Relaunch from clean public Git history after the pre-public 0.3.18 soft
  release.
• Keep the 0.3.18 OSS launch cleanup content: agent-neutral docs, Hermes
  activation support, Gemini activation removal, moved provenance/limitations
  docs, and public release-hygiene hardening.