feat(core): implement Phase 1 analysis pipeline with CLI integration

[millareskenneth]

• Add analyze() function orchestrating file scanning, parsing, extraction, and graph building
• Implement file scanner with TypeScript/JavaScript detection and ignore list support
• Add AST parser using swc for extracting import statements from source files
• Implement dependency extractor with relative path resolution and extension handling
• Add graph builder creating nodes, edges, and detecting isolated files and cycles
• Implement terminal renderer with ASCII output and optional external package filtering
• Update CLI to invoke analysis pipeline with --show-external and --ignore options
• Add comprehensive test suites for parser, scanner, and graph builder
• Update tsup config to generate both ESM and CommonJS outputs with proper entry points
• Update package exports to include analyze function and type definitions