P0.1: Repository and module setup

Go module, Makefile with standard targets, golangci-lint v2 config,
CLAUDE.md, and empty CLI/agent binaries. Build, vet, and lint all pass.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,18 @@
+# Binaries
+/mcp
+/mcp-agent
+
+# Runtime data
+srv/
+
+# Database files
+*.db
+*.db-wal
+*.db-shm
+
+# IDE
+.idea/
+.vscode/
+
+# OS
+.DS_Store