Major refactoring: UUID-based storage, streaming architecture, and CLI improvements

This commit represents a significant architectural overhaul of vaultik:

Database Schema Changes:
- Switch files table to use UUID primary keys instead of path-based keys
- Add UUID primary keys to blobs table for immediate chunk association
- Update all foreign key relationships to use UUIDs
- Add comprehensive schema documentation in DATAMODEL.md
- Add SQLite busy timeout handling for concurrent operations

Streaming and Performance Improvements:
- Implement true streaming blob packing without intermediate storage
- Add streaming chunk processing to reduce memory usage
- Improve progress reporting with real-time metrics
- Add upload metrics tracking in new uploads table

CLI Refactoring:
- Restructure CLI to use subcommands: snapshot create/list/purge/verify
- Add store info command for S3 configuration display
- Add custom duration parser supporting days/weeks/months/years
- Remove old backup.go in favor of enhanced snapshot.go
- Add --cron flag for silent operation

Configuration Changes:
- Remove unused index_prefix configuration option
- Add support for snapshot pruning retention policies
- Improve configuration validation and error messages

Testing Improvements:
- Add comprehensive repository tests with edge cases
- Add cascade delete debugging tests
- Fix concurrent operation tests to use SQLite busy timeout
- Remove tolerance for SQLITE_BUSY errors in tests

Documentation:
- Add MIT LICENSE file
- Update README with new command structure
- Add comprehensive DATAMODEL.md explaining database schema
- Update DESIGN.md with UUID-based architecture

Other Changes:
- Add test-config.yml for testing
- Update Makefile with better test output formatting
- Fix various race conditions in concurrent operations
- Improve error handling throughout

Makefile

@@ -1,19 +1,27 @@
 .PHONY: test fmt lint build clean all
 
+# Version number
+VERSION := 0.0.1
+
 # Build variables
-VERSION := $(shell git describe --tags --always --dirty 2>/dev/null || echo "dev")
-COMMIT := $(shell git rev-parse HEAD 2>/dev/null || echo "unknown")
+GIT_REVISION := $(shell git rev-parse HEAD 2>/dev/null || echo "unknown")
 
 # Linker flags
 LDFLAGS := -X 'git.eeqj.de/sneak/vaultik/internal/globals.Version=$(VERSION)' \
-           -X 'git.eeqj.de/sneak/vaultik/internal/globals.Commit=$(COMMIT)'
+           -X 'git.eeqj.de/sneak/vaultik/internal/globals.Commit=$(GIT_REVISION)'
 
 # Default target
 all: test
 
 # Run tests
 test: lint fmt-check
-	go test -v ./...
+	@echo "Running tests..."
+	@if ! go test -v -timeout 10s ./... 2>&1; then \
+		echo ""; \
+		echo "TEST FAILURES DETECTED"; \
+		echo "Run 'go test -v ./internal/database' to see database test details"; \
+		exit 1; \
+	fi
 
 # Check if code is formatted
 fmt-check: