refactor: scrub residual ScadaLink refs → ScadaBridge (env vars, config keys, assembly name, SQL login)

Renames the 13 SCADALINK_* runtime env vars → SCADABRIDGE_*, the ScadaLink__
.NET config keys → ScadaBridge__, the stale ScadaLink.Host.exe assembly name
→ ZB.MOM.WW.ScadaBridge.Host.exe, the scadalink_app SQL login → scadabridge_app,
and residual identifiers/comments/docs. Migration records (prior rename
tooling/design, DB-rename helper, this scrub script) carved out.

Adds tools/scrub-scadalink-refs.sh.

docs/requirements/HighLevelReqs.md

@@ -531,7 +531,7 @@ Sites log operational events locally, including:
 - The CLI sends user credentials via HTTP Basic Auth. The server authenticates against **LDAP/AD** and resolves roles before dispatching commands to the ManagementActor.
 - CLI commands mirror all Management Service operations: templates, instances, sites, data connections, deployments, external systems, notifications, security (API keys and role mappings), audit log queries, and health status.
 - Output is **JSON by default** (machine-readable, suitable for scripting) with an optional `--format table` flag for human-readable tabular output.
-- Configuration is resolved from command-line options, **environment variables** (`SCADALINK_MANAGEMENT_URL`, `SCADALINK_FORMAT`), or a **configuration file** (`~/.scadabridge/config.json`).
+- Configuration is resolved from command-line options, **environment variables** (`SCADABRIDGE_MANAGEMENT_URL`, `SCADABRIDGE_FORMAT`), or a **configuration file** (`~/.scadabridge/config.json`).
 - The CLI is a separate executable from the Host binary — it is deployed on any machine with HTTP access to a central node.
 
 ## 14. General Conventions