docs(admin-config-tool): commit spec docs and example configs

design.md, research.md (new), brief.md and requirements.md (updated
during spec authoring: Req 1.6 resolved/superseded by bundling, Req
5.5 added, Req 4.3/4.4 extended for limits.yaml) had been sitting
uncommitted since before implementation began -- the entire 18-task
implementation was built against these documents without them ever
landing in git.

src/configs/*.yaml + schema/*.schema.json: the example config
directory and bundled JSON schemas most of the test suite reads as
"real repo fixtures" (test_config_build.py, test_mapping.py,
test_validation.py, etc.) were likewise never committed -- those
tests would silently skip (skipif guards) rather than run for anyone
else checking out this branch.

src/configs/schema/resources.schema.json

@@ -0,0 +1,41 @@
+{
+  "type": "object",
+  "properties": {
+    "resources": {
+      "type": "array",
+      "items": {
+        "type": "object",
+        "properties": {
+          "name":        { "type": "string" },
+          "type":        { "type": "string", "enum": ["numeric", "boolean", "string"] },
+          "interval":    { "type": "integer" },
+          "order":       { "type": "string", "enum": ["increase", "decrease", "na"] },
+          "consumable":  { "type": "boolean" },
+          "release":     { "type": "boolean" },
+          "description": { "type": "string" },
+          "resourcemap": {
+            "type": "array",
+            "items": {
+              "type": "object",
+              "properties": {
+                "value": {
+                  "oneOf": [
+                    { "type": "number" },
+                    { "type": "string" },
+                    { "type": "boolean" }
+                  ]
+                },
+                "location": {
+                  "type": "array",
+                  "items": { "type": "string" }
+                }
+              }
+            }
+          }
+        },
+        "required": ["name", "type"]
+      }
+    }
+  },
+  "required": ["resources"]
+}