feat(councils): add preflight, schema-driven outputs, and artifact reporting

README.md

@@ -522,7 +522,7 @@ pnpm tui:fs
 | `/status` | Show session info |
 | `/tools` | Show authoritative runtime tool list for this session |
 | `/research <task>` | Delegate a task to `agent_configs.research` |
-| `/council <task>` | Run dual D/P councils pipeline with bridge+meta merge |
+| `/council <task>` | Run dual D/P councils pipeline with bridge+meta merge (brief in TUI, full artifacts saved to disk) |
 | `/compact` | Compact conversation context |
 | `/usage` | Show token usage and cost |
 | `/context` | Show estimated context-window usage |
@@ -631,6 +631,22 @@ Run from chat:
 /council design a 30-day plan to cut CI flakiness by 50%
 ```
 
+By default, `/council` prints a concise execution brief in the TUI and persists full artifacts under:
+
+```text
+~/.local/share/flynn/councils/
+```
+
+When `FLYNN_DATA_DIR` is set, artifacts are written to:
+
+```text
+${FLYNN_DATA_DIR}/councils/
+```
+
+Each run saves:
+- `*.md` summary report (brief + full conversation trace + raw JSON block)
+- `*.json` full structured `CouncilRunResult`
+
 Or via tools:
 
 ```json