chore: bump version to 4.5.0

Bug fixes:
- Fix inverted pager detection logic (returned error instead of path)
- Fix repo.Clone ignoring destination directory parameter
- Fix sheet loading using append on pre-sized slices
- Clean up partial files on copy failure
- Trim whitespace from editor config

Security:
- Add path traversal protection for cheatsheet names

Performance:
- Move regex compilation outside search loop
- Replace string concatenation with strings.Join in search

Build:
- Remove go:generate; embed config and usage as string literals
- Parallelize release builds
- Add fuzz testing infrastructure

Testing:
- Improve test coverage from 38.9% to 50.2%
- Add fuzz tests for search, filter, tags, and validation

Documentation:
- Fix inaccurate code examples in HACKING.md
- Add missing --conf and --all options to man page
- Add ADRs for path traversal, env parsing, and search parallelization
- Update CONTRIBUTING.md to reflect project policy

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

internal/sheet/colorize_test.go

@@ -32,3 +32,29 @@ func TestColorize(t *testing.T) {
 		t.Errorf("failed to colorize sheet: want: %s, got: %s", want, s.Text)
 	}
 }
+
+// TestColorizeError tests the error handling in Colorize
+func TestColorizeError(_ *testing.T) {
+	// Create a sheet with content
+	sheet := Sheet{
+		Text:   "some text",
+		Syntax: "invalidlexer12345", // Use an invalid lexer that might cause issues
+	}
+
+	// Create a config with invalid formatter/style
+	conf := config.Config{
+		Formatter: "invalidformatter",
+		Style:     "invalidstyle",
+	}
+
+	// Store original text
+	originalText := sheet.Text
+
+	// Colorize should not panic even with invalid settings
+	sheet.Colorize(conf)
+
+	// The text might be unchanged if there was an error, or it might be colorized
+	// We're mainly testing that it doesn't panic
+	_ = sheet.Text
+	_ = originalText
+}