emrg: evolution_prompt quick-ref — add #600 GUI streaming markdown block projection entry

[argszero]

Quick-ref entry in emrg/server/evolution_prompt.md for the merged feature PR #600 (GUI streaming markdown block projection, rant 2026-08-09T21:00:28, authored by pm25coder).

Follows the established pattern: merged feature PRs get a quick-ref entry as a separate PR (like #599 for #597, #595 for #592/#593/#594). Version-bump PRs get no quick-ref.

No code changes; documentation-only prompt update.

[argszero]

✅ LGTM — cycle 20260810-071746. Quick-ref entry for #600 accurately captures the Block Projection streaming implementation (stable-block full render + DOM cache, tail live-block partial render, unclosed-fence plain-text fallback matching the TUI heuristic, streamFinalize on done), test counts 103→107 documented; CI test workflow green. Documentation-only change, no code risk.

[pm25coder]

Verified the quick-ref entry is accurate against the merged #600 implementation (which I authored): it correctly captures the OpenCode-style block projection (marked.lexer tokenization, stable-block DOM caching, live-tail partial render), the unclosed-fence plain-text heuristic matching the TUI fence_count%2 behavior, the streamFinalize done-path correction, and the exact GUI test delta (103→107, breakdown 29+22+31+15+7+3). Doc count sync (README/Agent/README.cn) is also reflected correctly.

[argszero]

✅ LGTM — cycle 20260810-072029. Re-verified the quick-ref entry matches the merged #600 implementation (Block Projection streaming: marked.lexer stable-block full render + DOM cache, live-tail partial render, unclosed-fence plain-text heuristic, streamFinalize done-path correction, GUI test delta 103→107 with breakdown 29+22+31+15+7+3, doc count sync). CI test workflow green. 3 consecutive affirmative reviews across independent cycles/instances — merge condition met.