feat: implement Obsidian MCP Bundle MVP (Phase 1-3)

- Complete project setup with TypeScript, Jest, MCPB manifest
- Implement foundational infrastructure (CLI executor, logger, error handler)
- Add 9 file operation tools for User Story 1
- Full MCP protocol compliance with stdio transport
- Input validation and sanitization for security
- Comprehensive error handling with actionable messages
- Constitutional compliance: all 6 principles satisfied

MVP includes:
- obsidian_create_note, read, append, prepend, delete, move, rename, open, file_info
- Zod validation schemas for all parameters
- 30s timeout configuration with per-command overrides
- Stderr-only logging with sanitized output
- Graceful shutdown handling

Build: ✅ 0 errors, 0 vulnerabilities
Tasks: 48/167 complete (MVP milestone)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

assets/icon.png.placeholder

@@ -0,0 +1,12 @@
+# Icon Placeholder
+# 
+# This is a placeholder for the bundle icon.
+# To complete this task:
+# 1. Create a 512x512 PNG icon representing the Obsidian MCP Bundle
+# 2. Place it at assets/icon.png
+# 3. Remove this placeholder file
+#
+# Suggested icon concepts:
+# - Obsidian logo combined with AI/connection symbols
+# - Brain/network icon in Obsidian's purple color scheme
+# - Document/note icon with chat/conversation elements