Add deployment phase and Traefik compose override

Insert a new Phase 1 (deployment: Compose + Traefik on a server, marked
Done) between the base project and the OTel concepts phase, and shift
the old phases 1-10 to 2-11. Update summary, intro, README and CLAUDE.md
references (spoiler rules now target Phase 9, the bottleneck hunt).

Add docker-compose.traefik.yml: an override that fronts the gateway with
Traefik and Let's Encrypt and removes all other published host ports.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

docs/roadmap/phase-0.md

@@ -67,7 +67,7 @@ deliberate brokenness.
 
 ### Why TDD here, when the app itself doesn't matter
 
-The microservices are throwaway. The *properties* aren't. Everything from Phase 2
+The microservices are throwaway. The *properties* aren't. Everything from Phase 3
 onward assumes the system still behaves a specific way: seven real services in
 the path, async work genuinely off the request path, five hot accounts owning a
 third of the rows, and thirteen pathologies that actually degrade something. You
@@ -114,13 +114,13 @@ Done when `make test` is green three consecutive runs and
 ### Then, yourself
 
 1. **Read every service's `app.py` end to end.** You need to know this codebase
-   cold, because from Phase 2 onward you're modifying all seven services.
+   cold, because from Phase 3 onward you're modifying all seven services.
 2. **Run `make chaos-nightmare`, fire a 200-request burst from the frontend, and
    then try to figure out what's wrong using only `docker compose logs`.** Give it
    twenty real minutes. You will fail, and the specific way you fail — no timing,
    no causality, no cross-service correlation, a `X-Request-Id` that dies at the
    Redis Stream — is the motivation for everything that follows. Write down what
-   you wished you had. That list is your acceptance criteria for Phase 8.
+   you wished you had. That list is your acceptance criteria for Phase 9.
 
 **Done when:** `make test` is green three runs in a row, all nine acceptance
 criteria in the base spec pass, and you have that written list of frustrations.