Add Wave contract schemas for pipeline validation

JSON Schema definitions for all pipeline handover contracts
including issue analysis, research, enhancement, and sync flows.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.wave/contracts/publish-result.schema.json

@@ -0,0 +1,29 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "title": "Code Review Publish Result",
+  "description": "Result of publishing a code review comment on a pull request",
+  "type": "object",
+  "required": ["comment_url", "pr_number"],
+  "properties": {
+    "comment_url": {
+      "type": "string",
+      "format": "uri",
+      "description": "URL to the posted review comment"
+    },
+    "pr_number": {
+      "type": "integer",
+      "minimum": 1,
+      "description": "PR number that was reviewed"
+    },
+    "repository": {
+      "type": "string",
+      "pattern": "^[^/]+/[^/]+$",
+      "description": "Repository full name (owner/repo)"
+    },
+    "summary": {
+      "type": "string",
+      "description": "Brief summary of the review"
+    }
+  },
+  "additionalProperties": true
+}