Point dta_webapp webroot at realpath.app paths (closes #12) (#13)

## Summary
- Change `dta_webapp` `webroot_pattern` from `/var/www/{env}.app.ditchtheagent/html` → `/var/www/{env}.realpath.app/html`
- Update `IMPLEMENTATION.md` references to match
- **web-static:** before `compose up`, `docker rm -f` any container publishing the static host ports (`docker ps --filter publish=<port>`), then force-recreate when cleanup ran — clears orphan/legacy binders while keeping the same ports

Closes #12

Coordinates with [dta_webapp#48](Ditch_The_Agent/dta_webapp#48) / [PR #49](Ditch_The_Agent/dta_webapp#49) (`build:beta`/`build:prod` write to the same dirs; prod uses `prod.realpath.app`).

## Test plan
- [ ] Confirm `app_catalog.dta_webapp.webroot_pattern` expands to beta/prod realpath paths
- [ ] On a host with a leftover container on 8080/8081, run deploy and confirm it is removed and web-static rebinds
- [ ] After merge, redeploy `dta_webapp` beta (and prod when ready) and verify files under `/var/www/{env}.realpath.app/html`
- [ ] Hit web-static ports and confirm new build content servedReviewed-on: #13

inventory/group_vars/all.yml

@@ -77,7 +77,7 @@ app_catalog:
     subdir: ditch-the-agent
     # Document root served by nginx and written by `npm run build:<env>`.
     # {env} is replaced with the entry's env (beta/prod).
-    webroot_pattern: "/var/www/{env}.app.ditchtheagent/html"
+    webroot_pattern: "/var/www/{env}.realpath.app/html"
     # deploy runs `npm ci` then `npm run build:<env>`; that script writes to
     # {{ web_static_root }}/<env>_dta_webapp (beta/prod), served by web-static.
   scha: