docs: concept annexation, provider/reference docs, ACT-1 groundwork

Mosaic concepts pages now own the adapted content; source/license
metadata under docs/reference/concepts. Adds ACT-1 agent-context
planning capture, pinned concept test package + preparation utility,
foundation observation notes (durability, evidence, federation,
onboarding, workflow), and the #1495 consolidation assessment.
TOOLS.md updated for the host-dev launcher.

docs/TOOLS.md

@@ -58,6 +58,22 @@ for the M13 plain governed TUI. `--auth <account>` injects
 `auth.<account>.json` (beside the active credential file) as the launch's
 `PI_AUTH_FILE`; a missing/invalid account refuses (M19).
 
+For native repository development, opt in with a **leading** `--host-dev`:
+
+```bash
+scripts/agent.sh --host-dev darkwing [--fresh] [--check] [--soul FILE] [--constitution FILE] [--user FILE]
+```
+
+This mode delegates to `scripts/agent-host-dev.sh`, uses host Pi and repository
+tools/skills plus the development goal extension, and keeps its own sessions
+under `.pi/state/<name>/`. It uses native Pi authentication and does not run
+container release alignment or apply managed seat role ceilings. It is a host
+development session, not a sandboxed worker. Container-only flags such as
+`--auth`, `--mission`, and `--tools` are rejected in this mode. Omitting
+`--host-dev` retains the existing container lifecycle and policy checks;
+container failures never trigger a host fallback. Darkwing's agent-local shim
+selects host development explicitly. See `agents/darkwing/README.md`.
+
 ## Auth (credentials)
 
 Credential checkpoint over pi's auth model (one `auth.json` keyed by