feat: add types.Category, data models, and browserdata.Data (#512)

* feat: add new types.Category, data models, and browserdata.Data

Phase 1 of architecture refactoring (RFC-001/RFC-002):

- types/category.go: Category enum (9 values) replacing DataType (22 values)
  with String(), IsSensitive(), AllCategories, NonSensitiveCategories()
- types/models.go: browser-agnostic data models (LoginEntry, CookieEntry,
  BookmarkEntry, HistoryEntry, DownloadEntry, CreditCardEntry, StorageEntry,
  ExtensionEntry) — no encrypted fields, no browser prefixes
- types/category_test.go: tests for Category methods
- browserdata/browser_data.go: new Data struct with typed slices,
  coexists with old BrowserData during migration

* docs: replace Coveralls badge with Codecov in README

* fix: apply review suggestions (is_http_only tag, json tags on Data)

types/category.go

@@ -0,0 +1,71 @@
+package types
+
+// Category represents a kind of browser data.
+// It is browser-agnostic — a password is a password regardless of which browser it came from.
+type Category int
+
+const (
+	Password Category = iota
+	Cookie
+	Bookmark
+	History
+	Download
+	CreditCard
+	Extension
+	LocalStorage
+	SessionStorage
+)
+
+// AllCategories returns all supported data categories.
+var AllCategories = []Category{
+	Password, Cookie, Bookmark, History, Download,
+	CreditCard, Extension, LocalStorage, SessionStorage,
+}
+
+// String returns the human-readable name of the category.
+func (c Category) String() string {
+	switch c {
+	case Password:
+		return "password"
+	case Cookie:
+		return "cookie"
+	case Bookmark:
+		return "bookmark"
+	case History:
+		return "history"
+	case Download:
+		return "download"
+	case CreditCard:
+		return "creditcard"
+	case Extension:
+		return "extension"
+	case LocalStorage:
+		return "localstorage"
+	case SessionStorage:
+		return "sessionstorage"
+	default:
+		return "unknown"
+	}
+}
+
+// IsSensitive returns whether the category contains sensitive data
+// that requires explicit opt-in to export.
+func (c Category) IsSensitive() bool {
+	switch c {
+	case Password, Cookie, CreditCard:
+		return true
+	default:
+		return false
+	}
+}
+
+// NonSensitiveCategories returns categories that are safe to export by default.
+func NonSensitiveCategories() []Category {
+	var cats []Category
+	for _, c := range AllCategories {
+		if !c.IsSensitive() {
+			cats = append(cats, c)
+		}
+	}
+	return cats
+}

types/category_test.go

@@ -0,0 +1,52 @@
+package types
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCategory_String(t *testing.T) {
+	tests := []struct {
+		cat  Category
+		want string
+	}{
+		{Password, "password"},
+		{Cookie, "cookie"},
+		{Bookmark, "bookmark"},
+		{History, "history"},
+		{Download, "download"},
+		{CreditCard, "creditcard"},
+		{Extension, "extension"},
+		{LocalStorage, "localstorage"},
+		{SessionStorage, "sessionstorage"},
+		{Category(999), "unknown"},
+	}
+	for _, tt := range tests {
+		assert.Equal(t, tt.want, tt.cat.String())
+	}
+}
+
+func TestCategory_IsSensitive(t *testing.T) {
+	sensitive := []Category{Password, Cookie, CreditCard}
+	for _, c := range sensitive {
+		assert.True(t, c.IsSensitive(), "%s should be sensitive", c)
+	}
+
+	notSensitive := []Category{Bookmark, History, Download, Extension, LocalStorage, SessionStorage}
+	for _, c := range notSensitive {
+		assert.False(t, c.IsSensitive(), "%s should not be sensitive", c)
+	}
+}
+
+func TestAllCategories(t *testing.T) {
+	assert.Len(t, AllCategories, 9)
+}
+
+func TestNonSensitiveCategories(t *testing.T) {
+	cats := NonSensitiveCategories()
+	assert.Len(t, cats, 6)
+	for _, c := range cats {
+		assert.False(t, c.IsSensitive())
+	}
+}

types/models.go

@@ -0,0 +1,71 @@
+package types
+
+import "time"
+
+// LoginEntry represents a single saved login credential.
+type LoginEntry struct {
+	URL       string    `json:"url"        csv:"url"`
+	Username  string    `json:"username"   csv:"username"`
+	Password  string    `json:"password"   csv:"password"`
+	CreatedAt time.Time `json:"created_at" csv:"created_at"`
+}
+
+// CookieEntry represents a single browser cookie.
+type CookieEntry struct {
+	Host       string    `json:"host"        csv:"host"`
+	Path       string    `json:"path"        csv:"path"`
+	Name       string    `json:"name"        csv:"name"`
+	Value      string    `json:"value"       csv:"value"`
+	IsSecure   bool      `json:"is_secure"   csv:"is_secure"`
+	IsHTTPOnly bool      `json:"is_http_only" csv:"is_http_only"`
+	ExpireAt   time.Time `json:"expire_at"   csv:"expire_at"`
+	CreatedAt  time.Time `json:"created_at"  csv:"created_at"`
+}
+
+// BookmarkEntry represents a single browser bookmark.
+type BookmarkEntry struct {
+	Name      string    `json:"name"       csv:"name"`
+	URL       string    `json:"url"        csv:"url"`
+	Folder    string    `json:"folder"     csv:"folder"`
+	CreatedAt time.Time `json:"created_at" csv:"created_at"`
+}
+
+// HistoryEntry represents a single browser history record.
+type HistoryEntry struct {
+	URL        string    `json:"url"         csv:"url"`
+	Title      string    `json:"title"       csv:"title"`
+	VisitCount int       `json:"visit_count" csv:"visit_count"`
+	LastVisit  time.Time `json:"last_visit"  csv:"last_visit"`
+}
+
+// DownloadEntry represents a single browser download record.
+type DownloadEntry struct {
+	URL        string    `json:"url"         csv:"url"`
+	TargetPath string    `json:"target_path" csv:"target_path"`
+	TotalBytes int64     `json:"total_bytes" csv:"total_bytes"`
+	StartTime  time.Time `json:"start_time"  csv:"start_time"`
+	EndTime    time.Time `json:"end_time"    csv:"end_time"`
+}
+
+// CreditCardEntry represents a single saved credit card.
+type CreditCardEntry struct {
+	Name     string `json:"name"      csv:"name"`
+	Number   string `json:"number"    csv:"number"`
+	ExpMonth string `json:"exp_month" csv:"exp_month"`
+	ExpYear  string `json:"exp_year"  csv:"exp_year"`
+}
+
+// StorageEntry represents a single key-value pair from local or session storage.
+type StorageEntry struct {
+	URL   string `json:"url"   csv:"url"`
+	Key   string `json:"key"   csv:"key"`
+	Value string `json:"value" csv:"value"`
+}
+
+// ExtensionEntry represents a single browser extension.
+type ExtensionEntry struct {
+	Name        string `json:"name"        csv:"name"`
+	ID          string `json:"id"          csv:"id"`
+	Description string `json:"description" csv:"description"`
+	Version     string `json:"version"     csv:"version"`
+}