chore(standards): replace local standards/ with stub pointing to AzureLocal/platform

Phase 1 of the platform rollout (ADR-0002). Deletes the local copies of
org-wide standards docs and replaces them with a STANDARDS.md stub linking
to the canonical source in AzureLocal/platform/standards/.

The previous .md files were duplicates of azurelocal.github.io/standards/
that had drifted. The canonical copies now live (and are authored) in
AzureLocal/platform; this repo consumes them by reference.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: Kristopher Turner

STANDARDS.md

@@ -0,0 +1,9 @@
+# Standards
+
+AzureLocal organization standards are maintained centrally in the [`AzureLocal/platform`](https://github.com/AzureLocal/platform) repository. This repo does **not** keep a local copy.
+
+- **Canonical source**: [`AzureLocal/platform/standards/`](https://github.com/AzureLocal/platform/tree/main/standards)
+- **Rendered for humans**: [azurelocal.cloud/standards](https://azurelocal.cloud/standards/)
+- **Governance**: [ADR-0002 — Standards as single source of truth](https://github.com/AzureLocal/platform/blob/main/decisions/0002-standards-single-source.md)
+
+Changes to any standard are PRs against `AzureLocal/platform`, not against this repo.