chore(manifest): re-source mcp.md from stackbilt-web; drop compass-governance-api

Compass was removed as a standalone product; its governance API doc
described an internal RPC service that's been absorbed into the
scaffold pipeline. The compass-governance-api.md entry never produced
a synced file in src/content/docs/ (the source no longer matched
current architecture), so this is a manifest-only cleanup.

The MCP page now sources from stackbilt-web (canonical post-
consolidation, just-merged stackbilt-web/docs/mcp.md describes the
live mcp.stackbilt.dev/mcp gateway with current OAuth + service-
binding architecture) rather than the legacy edgestack_v2 file
(which described a decommissioned stackbilt.dev/mcp endpoint with
Compass JWT auth).

After this commit the edgestack-legacy source group is empty, so
removed too. All platform docs now flow from stackbilt-web
(canonical), charter (CLI), or img-forge (image gateway).

Bumped manifest version 2 → 3.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: Kurt Overmier

docs-manifest.json

@@ -1,6 +1,6 @@
 {
   "$schema": "Stackbilt docs sync manifest — maps product repos to doc site pages",
-  "version": 2,
+  "version": 3,
   "contentDir": "src/content/docs",
   "org": "Stackbilt-dev",
   "sources": {
@@ -27,6 +27,13 @@
           "color": "#f472b6",
           "tag": "04"
         },
+        "mcp.md": {
+          "source": "docs/mcp.md",
+          "section": "platform",
+          "order": 5,
+          "color": "#22d3ee",
+          "tag": "05"
+        },
         "api-reference.md": {
           "source": "docs/api-reference.md",
           "section": "platform",
@@ -43,25 +50,6 @@
         }
       }
     },
-    "edgestack-legacy": {
-      "repo": "edgestack_v2",
-      "pages": {
-        "mcp.md": {
-          "source": "docs/mcp.md",
-          "section": "platform",
-          "order": 5,
-          "color": "#22d3ee",
-          "tag": "05"
-        },
-        "compass-governance-api.md": {
-          "source": "docs/compass-governance-api.md",
-          "section": "platform",
-          "order": 8,
-          "color": "#22d3ee",
-          "tag": "08"
-        }
-      }
-    },
     "img-forge": {
       "repo": "img-forge",
       "pages": {