Add contractors by residence endpoint and Bruno API collection

- Add GET /contractors/by-residence/:residence_id/ endpoint
- Create comprehensive Bruno API collection (89 endpoints)
- Collection covers all API endpoints with Local and Dev environments

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

bruno-collections/casera-api/Contractors/Create Contractor.bru

@@ -0,0 +1,28 @@
+meta {
+  name: Create Contractor
+  type: http
+  seq: 2
+}
+
+post {
+  url: {{api_url}}/contractors/
+  body: json
+  auth: none
+}
+
+headers {
+  Authorization: Token {{auth_token}}
+}
+
+body:json {
+  {
+    "name": "John's Plumbing",
+    "company": "John's Plumbing Co",
+    "phone": "555-123-4567",
+    "email": "john@plumbing.com",
+    "address": "123 Main St",
+    "notes": "Available weekends",
+    "specialty_ids": [1, 2],
+    "residence_ids": [1]
+  }
+}