Archive staging-environments change; update local-dev spec

Staging environments are live and fully operational. Marks the remaining
verification tasks complete, syncs the delta spec to main specs, and
archives the change.

Also adds a "When to Use Local vs. Staging" reference table to the
local-dev-environment spec so the boundary between the two environments
is documented in one place.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

openspec/changes/archive/2026-05-17-staging-environments/tasks.md

@@ -8,7 +8,7 @@
 - [x] 2.1 Create `infrastructure/docker-compose.staging.yml` with staging journal (port 3100), planner (port 3101), memory limits (256MB), and `trails_staging` database URL
 - [x] 2.2 Create `infrastructure/staging.env.template` documenting required staging environment variables (DOMAIN, DATABASE_URL, JWT_SECRET, SESSION_SECRET)
 - [x] 2.3 Add a shared Docker network (`trails-shared`) to production `docker-compose.yml` so staging can reach BRouter and PostgreSQL
-- [ ] 2.4 Verify staging containers start with `docker compose -f docker-compose.staging.yml -p trails-staging up -d` on the server
+- [x] 2.4 Verify staging containers start with `docker compose -f docker-compose.staging.yml -p trails-staging up -d` on the server
 
 ## 3. Caddy Wildcard Routing
 
@@ -16,7 +16,7 @@
 - [x] 3.2 Add `planner.staging.trails.cool` site block proxying to planner on port 3101
 - [x] 3.3 Add `import sites/*.caddyfile` to the main Caddyfile so per-PR site blocks can be dropped in and picked up on reload
 - [x] 3.4 Define the per-PR Caddyfile snippet template the cd-staging workflow writes for each preview (host = `pr-<N>.staging.trails.cool`, upstream = `host.docker.internal:<port>`, port = `3200 + 2N`)
-- [ ] 3.5 Reload Caddy and verify staging routes work with `curl -sf https://staging.trails.cool/api/health`
+- [x] 3.5 Reload Caddy and verify staging routes work with `curl -sf https://staging.trails.cool/api/health`
 
 ## 4. GitHub Actions Workflow
 
@@ -30,7 +30,7 @@
 
 - [x] 5.1 Create a scheduled cleanup job (weekly cron in GitHub Actions or pg-boss on the server) that lists running `trails-pr-*` containers, checks PR status via `gh pr view`, and tears down orphans
 - [x] 5.2 Add memory limits (`deploy.resources.limits.memory: 256m`) to staging containers in the compose override
-- [ ] 5.3 Test full lifecycle: open a test PR → verify preview deploys → push a commit → verify preview updates → close PR → verify teardown
+- [x] 5.3 Test full lifecycle: open a test PR → verify preview deploys → push a commit → verify preview updates → close PR → verify teardown
 
 ## 6. Documentation