feat(standards): add versioning + changelog standard, release templates, and Drone version guard

Add lib page 11 (SemVer contract, pre-1.0 rule, tag==version invariant, Keep a Changelog), the releasing wiki runbook, and canonical release templates (CHANGELOG.md, VERSION). Vendor them into the MCP bundle as templates/release + release.json and expose registry://release with list/get tools. Add a changelog component to the app template. Enforce the tag<->version contract in both Drone shapes: Type A check-version and the backfill loop verify pyproject version; Type B adds a VERSION guard step.

standards/mcp/release.json

@@ -0,0 +1,19 @@
+{
+  "project": "standards",
+  "template": "templates/release",
+  "invariant": "git tag == version file (enforced by the Drone guard)",
+  "components": [
+    {
+      "kind": "changelog",
+      "path": "CHANGELOG.md",
+      "placeholder": "",
+      "description": "Keep a Changelog skeleton: one [Unreleased] section + compare links."
+    },
+    {
+      "kind": "version-file",
+      "path": "VERSION",
+      "placeholder": "",
+      "description": "Single-line SemVer source of truth for services and sites."
+    }
+  ]
+}