feat: rename rails/ to tools/ and add service tool suites

Rename the `rails/` directory to `tools/` for agent discoverability —
agents frequently failed to locate helper scripts due to the non-intuitive
directory name. Add backward-compat symlink `rails/ → tools/`.

New tool suites:
- Authentik: auth-token, user-list, user-create, group-list, app-list,
  flow-list, admin-status (8 scripts)
- Coolify: team-list, project-list, service-list, service-status, deploy,
  env-set (7 scripts)
- Woodpecker: pipeline-list, pipeline-status, pipeline-trigger (3 stubs)
- GLPI: session-init, computer-list, ticket-list, ticket-create, user-list
  (6 scripts)
- Health: stack-health.sh — stack-wide connectivity check

Infrastructure:
- Shared credential loader at tools/_lib/credentials.sh
- install.sh creates symlink + chmod on tool scripts
- All ~253 rails/ path references updated across 68+ files

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

README.md

@@ -103,7 +103,7 @@ You can still launch runtimes directly (`claude`, `codex`, etc.) — thin runtim
 ├── bin/                   ← CLI tools (mosaic, mosaic-init, mosaic-doctor, etc.)
 ├── dist/                  ← Bundled wizard (mosaic-wizard.mjs)
 ├── guides/                ← Operational guides
-├── rails/                 ← Quality rails, git scripts, portainer scripts
+├── tools/                 ← Tool suites: git, portainer, authentik, coolify, codex, etc.
 ├── runtime/               ← Runtime adapters + runtime-specific references
 │   ├── claude/CLAUDE.md
 │   ├── claude/RUNTIME.md