Handle folder name input for copier

[tirthbodawala]

1. Copier Smart Defaults

Enhance user experience by automatically deriving project_name and project_slug from the destination folder name, reducing friction during project creation.

Changes:

• Use _copier_conf.dst_path.name to extract folder name
• project_name defaults to folder name (title-cased, spaces for separators)
  • "my-awesome-project" → "My Awesome Project"
  • "data_processor" → "Data Processor"
  • "backend-api-v2" → "Backend Api V2"
• project_slug defaults directly to folder name
• package_name automatically converts hyphens to underscores
• Updated success message to use dynamic project_slug
• Cross-platform compatible using Path.name property

Documentation:

• Added "Smart Defaults" section in Quick Start with examples
• Updated Configuration Options to clarify default behaviors
• Included examples showing the transformation patterns

2. AI Finish Task Non-Interactive by Default

Make ai-finish-task non-interactive by default for better AI agent and automation workflows. Running the command implies intent to finish.

Changes:

• Set --yes default to True (skip prompts by default)
• Added --interactive/-i flag to opt back into prompts if needed
• Updated function signature default: yes=True
• Updated docstrings to reflect new behavior

Testing:

• Updated test_finish_task_yes_defaults_to_true (renamed from _to_false)
• Test now verifies prompts are skipped by default
• All 219 tests passing with 100% coverage
• Verified copier with multiple naming patterns

Both improvements optimize the common case while preserving flexibility for edge cases and explicit user control when needed.