Add mcp-master binary and build target

New cmd/mcp-master/ entry point following the agent pattern:
cobra CLI with --config, version, and server commands.

Makefile: add mcp-master target, update all and clean targets.
Example config: deploy/examples/mcp-master.toml with all sections.

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

Makefile

@@ -8,6 +8,9 @@ mcp:
 mcp-agent:
 	CGO_ENABLED=0 go build $(LDFLAGS) -o mcp-agent ./cmd/mcp-agent
 
+mcp-master:
+	CGO_ENABLED=0 go build $(LDFLAGS) -o mcp-master ./cmd/mcp-master
+
 build:
 	go build ./...
 
@@ -30,6 +33,6 @@ proto-lint:
 	buf breaking --against '.git#branch=master,subdir=proto'
 
 clean:
-	rm -f mcp mcp-agent
+	rm -f mcp mcp-agent mcp-master
 
-all: vet lint test mcp mcp-agent
+all: vet lint test mcp mcp-agent mcp-master