Feature: Exclusion Patterns (--exclude) for Safe Cleanup

[tejaswankalluri]

Problem:
The current cleanup logic is broad (based on age or type). Users often have specific "pet" resources (e.g., a stopped postgres container with development data, or a base image) that they never want to delete, even if it falls within the cleanup criteria. Currently, they have to clean manually or risk losing these resources.

Proposed Solution:
Add an --exclude <pattern> flag that allows users to specify patterns for resources to be ignored during the scan and clean process.

Requirements:

1. Multiple Exclusions: Support multiple flags in one command.
   • Example: docklean --all --exclude "prod-*" --exclude "my-local-db"
2. Pattern Matching: Support standard glob patterns (e.g., *, ?) or regex for flexible matching against resource names/IDs.
3. Scope: The exclusion should apply to all resource types being scanned (Containers, Images, Volumes, Networks).

Expected Outcome:

• Resources matching the provided patterns are completely omitted from the scan results.
• These resources are never removed, regardless of their age or status.
• The summary output should ideally (optional but nice) mention that some items were excluded by user request.

Implementation Hints:

• Update src/args.ts to parse --exclude as a string array.
• Update src/scan.ts to filter items immediately after fetching from Docker, before applying age filters.