Refactor Start node UI to User Input and optimize EntryNodeContainer

[lyzno1]

Summary

• Refactor Start node display from "Start" to "User Input" in UI layer
• Create unified EntryNodeContainer for both Start and Trigger nodes
• Optimize indicator component to remove duplicate implementation

Changes

• Rename TriggerContainer to EntryNodeContainer with support for both node types
• Update English translations for Start → User Input
• Differentiate display: Start shows "START" without indicator, Trigger shows "TRIGGER" with indicator
• Restore simplified indicator style (green border + fill only)

Test Plan

• New workflow creation shows "User Input"
• Start nodes display "START" without status indicator
• Trigger nodes display "TRIGGER" with status indicator
• All existing functionality preserved