[#181] add AGENTS.md (#183)

- add AGENTS.md file for ai agents
- link sync-data-relational/SKILL.md
- add additional information for running in cursor

Author: chanhyeong

AGENTS.md

@@ -0,0 +1,12 @@
+# AGENTS
+
+## sync-data-relational
+- Skill doc: @.claude/skills/sync-data-relational/SKILL.md
+- Role: Analyze spring-data-relational version changes and outline any required actions for this project.
+- When to use: Whenever a spring-data-relational upgrade/sync is requested or we need to assess related impact.
+- Procedure:
+  1. Check BOM version (`gradle.properties`) and confirm target Spring Boot/Data alignment.
+  2. Fetch GitHub compare diff via `curl -L https://github.com/spring-projects/spring-data-relational/compare/{old}...{new}.diff` (Agent Mode + network perm).
+  3. Parse diff to list critical API changes (e.g., deprecations in `JdbcAggregateOperations`, repository adjustments) and dependency upgrades.
+  4. Search local code for affected symbols (e.g., deprecated template APIs, specific driver versions) and note required actions.
+  5. Draft report + TODOs covering impact, doc updates, and test guidance.