chore: move business tooling out of the public library; tidy filestore naming

Keep the public tree project-generic. Business/one-off tools, deployment
and business docs move to the private oo-workspace repo.

Moved to oo-workspace:
- cmd/ooscan, cmd/pdfamount, cmd/kontoblatt, cmd/kontolink
- internal/xlspipe (cutover-portugal workbook) -> oow workbook build
  (drops the --template/--title flags from oo docs put-xlsx)
- deploy/docker-compose.rclone-webdav.yml + docs/rclone-webdav.md
- docs/crm-associations.md

Removed GitHub-era leftovers:
- .github/workflows/release-please.yml, release-please-config.json,
  .release-please-manifest.json (tags are created on Gitea per SemVer)

Naming: the FileStore subsystem is now filestore_*.go (was file_*.go) to
match files_*.go (project Documents). Docs/AGENTS/README updated.

docs/community-server-db.md

@@ -3,7 +3,7 @@ type: reference
 status: current
 related:
   - README.md
-  - file_pg.go
+  - filestore_pg.go
   - docs/elasticsearch.md
 ---
 
@@ -11,7 +11,7 @@ related:
 
 ## Что это
 
-Бэкенд `pgStore` (`file_pg.go`) читает файлы и папки **напрямую из БД
+Бэкенд `pgStore` (`filestore_pg.go`) читает файлы и папки **напрямую из БД
 Community Server**, без HTTP-слоя. Реализует `FileStore` (`List`/`Stat`/
 `Download`) и `Searcher` по имени. Запись запрещена: все write-методы
 возвращают `ErrReadOnly`.