chore(catalog): release llm-security v7.8.0 — bump ref + README, refresh rollout brief

llm-security cut v7.8.0 (TRG/SIG/AST deep-scan scanners) and tagged `v7.8.0`
(commit 6d3c4b5) in its repo. Sync the marketplace coordinator:

- .claude-plugin/marketplace.json: source.ref v7.7.2 → v7.8.0 (installs track the
  real release; version-consistency gate → OK for llm-security).
- README.md: version label v7.7.2 → v7.8.0; scanner count 23 → 26 (+3: TRG/SIG/AST)
  in both the "Deterministic scanning" bullet and the stat line; tests 1822 → 1863.
- docs/state-version-rollout.md: mark llm-security STATE.md row DONE (it is tracked,
  not gitignored), add the missing playground-design-system row, and refresh the
  Workstream B run note (8 OK / 2 WARN; llm-security resolved this day).

Gate: `node scripts/check-versions.mjs` → 8 OK, 2 WARN (linkedin-studio,
ms-ai-architect — pre-existing, operator decision), 0 ERROR.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01V3s6WnubSSrFjAQTLQdVbG

.claude-plugin/marketplace.json

@@ -15,7 +15,7 @@
       "source": {
         "source": "url",
         "url": "https://git.fromaitochitta.com/open/llm-security.git",
-        "ref": "v7.7.2"
+        "ref": "v7.8.0"
       },
       "description": "Security scanning, auditing, and threat modeling for Claude Code projects. OWASP LLM Top 10 (2025) and Agentic AI Top 10."
     },