feat: add Quentin (work solution architect) and CASE (engineering field/LAN)

- Add Quentin as work-team lead agent for solution architecture & demos,
  with aws_sa repositioned as Quentin's exclusive subagent (tool, not peer)
- Add CASE as engineering lead agent for field/physical layer (LAN, hardware)
- Bump unified Neo4j schema to v2.4.0:
  - Add Solution and Demo node types under Quentin's domain
  - Update assistant ownership table with Quentin, CASE, and AWS SA scoping
- Update README and neo4j shared docs to reflect new team rosters and
  subagent boundaries

README.md

@@ -49,7 +49,9 @@ The lists below reflect what's currently in `prompts/{team}/` — the source of
 | **Ann** | Ann Handley | Content & Visibility |
 | **Jeffrey** | Jeffrey Gitomer | Proposals & Sales |
 | **Jarvis** | J.A.R.V.I.S. | Daily Execution |
-| **AWS SA** | — | Cloud architecture specialist (subagent) |
+| **Quentin** | Q (007 Quartermaster) | Solution architecture & demos |
+
+Work subagents (called as tools, not lead agents): **AWS SA** (cloud architecture, Quentin's exclusive subagent) and **tech_research** (technical investigation). See [docs/work/subagents.md](docs/work/subagents.md).
 
 ### Engineering Team
 | Assistant | Inspired By | Domain |
@@ -65,7 +67,7 @@ koios/
 ├── prompts/                          # Sent to LLM at runtime
 │   ├── personal/                     #   Personal assistants (lead agents)
 │   ├── work/                         #   Work assistants (lead agents)
-│   │   └── subagents/                #     Team-scoped subagents (e.g. aws-sa)
+│   │   └── subagents/                #     Team-scoped subagents (aws-sa, research, tech_research)
 │   ├── engineering/                  #   Engineering assistants (lead agents)
 │   │   └── subagents/                #     Team-scoped subagents (research, tech_research)
 │   └── tools/                        #   Per-tool prompt snippets