refactor: consolidate inquire select functionality into select module

[echozyr2001]

Consolidate Inquire Select Functionality

Fixes #1126

Consolidate scattered inquire select operations into a single centralized module with consistent error handling and UX.

• Created forge_main::select module with builder pattern API
• Centralized error handling: cancellations → Ok(None)
• Unified render configuration with consistent icons (⇡, ⇣, ➤)
• Migrated all usage from ui.rs and update.rs

API

// Simple selection
ForgeSelect::select("Choose option", options).prompt()?

// Confirmation with default
ForgeSelect::confirm("Are you sure?").with_default(true).prompt()?

// Advanced configuration
ForgeSelect::select("Select model", models)
    .with_starting_cursor(index)
    .with_help_message("Custom help")
    .prompt()?

[tusharmath]

@echozyr2001 Thank you!