Run bd doctor at end of bd init to verify setup

Implements bd-zwtq: After bd init completes, run doctor diagnostics
to catch configuration problems before user encounters them in normal
workflow. If any warnings or errors are detected, show a summary with
issue names and messages, then direct user to run 'bd doctor --fix'.

This helps users immediately identify and fix setup issues like:
- Missing git hooks
- Unconfigured merge driver
- Missing agent documentation
- Metadata tracking not initialized

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

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

cmd/bd/init.go

@@ -396,6 +396,27 @@ With --no-db: creates .beads/ directory and issues.jsonl file instead of SQLite
 		}
 
 		fmt.Printf("Run %s to get started.\n\n", cyan("bd quickstart"))
+
+		// Run bd doctor diagnostics to catch setup issues early (bd-zwtq)
+		doctorResult := runDiagnostics(cwd)
+		// Check if there are any warnings or errors (not just critical failures)
+		hasIssues := false
+		for _, check := range doctorResult.Checks {
+			if check.Status != statusOK {
+				hasIssues = true
+				break
+			}
+		}
+		if hasIssues {
+			fmt.Printf("%s Setup incomplete. Some issues were detected:\n", yellow("⚠"))
+			// Show just the warnings/errors, not all checks
+			for _, check := range doctorResult.Checks {
+				if check.Status != statusOK {
+					fmt.Printf("  • %s: %s\n", check.Name, check.Message)
+				}
+			}
+			fmt.Printf("\nRun %s to see details and fix these issues.\n\n", cyan("bd doctor --fix"))
+		}
 	},
 }