Initial commit: Beads issue tracker with security fixes

Core features:
- Dependency-aware issue tracking with SQLite backend
- Ready work detection (issues with no open blockers)
- Dependency tree visualization
- Cycle detection and prevention
- Full audit trail
- CLI with colored output

Security and correctness fixes applied:
- Fixed SQL injection vulnerability in UpdateIssue (whitelisted fields)
- Fixed race condition in ID generation (added mutex)
- Fixed cycle detection to return full paths (not just issue IDs)
- Added cycle prevention in AddDependency (validates before commit)
- Added comprehensive input validation (priority, status, types, etc.)
- Fixed N+1 query in GetBlockedIssues (using GROUP_CONCAT)
- Improved query building in GetReadyWork (proper string joining)
- Fixed P0 priority filter bug (using Changed() instead of value check)

All critical and major issues from code review have been addressed.

🤖 Generated with Claude Code

internal/types/types.go

@@ -0,0 +1,190 @@
+package types
+
+import (
+	"fmt"
+	"time"
+)
+
+// Issue represents a trackable work item
+type Issue struct {
+	ID                 string     `json:"id"`
+	Title              string     `json:"title"`
+	Description        string     `json:"description"`
+	Design             string     `json:"design,omitempty"`
+	AcceptanceCriteria string     `json:"acceptance_criteria,omitempty"`
+	Notes              string     `json:"notes,omitempty"`
+	Status             Status     `json:"status"`
+	Priority           int        `json:"priority"`
+	IssueType          IssueType  `json:"issue_type"`
+	Assignee           string     `json:"assignee,omitempty"`
+	EstimatedMinutes   *int       `json:"estimated_minutes,omitempty"`
+	CreatedAt          time.Time  `json:"created_at"`
+	UpdatedAt          time.Time  `json:"updated_at"`
+	ClosedAt           *time.Time `json:"closed_at,omitempty"`
+}
+
+// Validate checks if the issue has valid field values
+func (i *Issue) Validate() error {
+	if len(i.Title) == 0 {
+		return fmt.Errorf("title is required")
+	}
+	if len(i.Title) > 500 {
+		return fmt.Errorf("title must be 500 characters or less (got %d)", len(i.Title))
+	}
+	if i.Priority < 0 || i.Priority > 4 {
+		return fmt.Errorf("priority must be between 0 and 4 (got %d)", i.Priority)
+	}
+	if !i.Status.IsValid() {
+		return fmt.Errorf("invalid status: %s", i.Status)
+	}
+	if !i.IssueType.IsValid() {
+		return fmt.Errorf("invalid issue type: %s", i.IssueType)
+	}
+	if i.EstimatedMinutes != nil && *i.EstimatedMinutes < 0 {
+		return fmt.Errorf("estimated_minutes cannot be negative")
+	}
+	return nil
+}
+
+// Status represents the current state of an issue
+type Status string
+
+const (
+	StatusOpen       Status = "open"
+	StatusInProgress Status = "in_progress"
+	StatusBlocked    Status = "blocked"
+	StatusClosed     Status = "closed"
+)
+
+// IsValid checks if the status value is valid
+func (s Status) IsValid() bool {
+	switch s {
+	case StatusOpen, StatusInProgress, StatusBlocked, StatusClosed:
+		return true
+	}
+	return false
+}
+
+// IssueType categorizes the kind of work
+type IssueType string
+
+const (
+	TypeBug     IssueType = "bug"
+	TypeFeature IssueType = "feature"
+	TypeTask    IssueType = "task"
+	TypeEpic    IssueType = "epic"
+	TypeChore   IssueType = "chore"
+)
+
+// IsValid checks if the issue type value is valid
+func (t IssueType) IsValid() bool {
+	switch t {
+	case TypeBug, TypeFeature, TypeTask, TypeEpic, TypeChore:
+		return true
+	}
+	return false
+}
+
+// Dependency represents a relationship between issues
+type Dependency struct {
+	IssueID     string         `json:"issue_id"`
+	DependsOnID string         `json:"depends_on_id"`
+	Type        DependencyType `json:"type"`
+	CreatedAt   time.Time      `json:"created_at"`
+	CreatedBy   string         `json:"created_by"`
+}
+
+// DependencyType categorizes the relationship
+type DependencyType string
+
+const (
+	DepBlocks      DependencyType = "blocks"
+	DepRelated     DependencyType = "related"
+	DepParentChild DependencyType = "parent-child"
+)
+
+// IsValid checks if the dependency type value is valid
+func (d DependencyType) IsValid() bool {
+	switch d {
+	case DepBlocks, DepRelated, DepParentChild:
+		return true
+	}
+	return false
+}
+
+// Label represents a tag on an issue
+type Label struct {
+	IssueID string `json:"issue_id"`
+	Label   string `json:"label"`
+}
+
+// Event represents an audit trail entry
+type Event struct {
+	ID        int64      `json:"id"`
+	IssueID   string     `json:"issue_id"`
+	EventType EventType  `json:"event_type"`
+	Actor     string     `json:"actor"`
+	OldValue  *string    `json:"old_value,omitempty"`
+	NewValue  *string    `json:"new_value,omitempty"`
+	Comment   *string    `json:"comment,omitempty"`
+	CreatedAt time.Time  `json:"created_at"`
+}
+
+// EventType categorizes audit trail events
+type EventType string
+
+const (
+	EventCreated           EventType = "created"
+	EventUpdated           EventType = "updated"
+	EventStatusChanged     EventType = "status_changed"
+	EventCommented         EventType = "commented"
+	EventClosed            EventType = "closed"
+	EventReopened          EventType = "reopened"
+	EventDependencyAdded   EventType = "dependency_added"
+	EventDependencyRemoved EventType = "dependency_removed"
+	EventLabelAdded        EventType = "label_added"
+	EventLabelRemoved      EventType = "label_removed"
+)
+
+// BlockedIssue extends Issue with blocking information
+type BlockedIssue struct {
+	Issue
+	BlockedByCount int      `json:"blocked_by_count"`
+	BlockedBy      []string `json:"blocked_by"`
+}
+
+// TreeNode represents a node in a dependency tree
+type TreeNode struct {
+	Issue
+	Depth     int  `json:"depth"`
+	Truncated bool `json:"truncated"`
+}
+
+// Statistics provides aggregate metrics
+type Statistics struct {
+	TotalIssues      int     `json:"total_issues"`
+	OpenIssues       int     `json:"open_issues"`
+	InProgressIssues int     `json:"in_progress_issues"`
+	ClosedIssues     int     `json:"closed_issues"`
+	BlockedIssues    int     `json:"blocked_issues"`
+	ReadyIssues      int     `json:"ready_issues"`
+	AverageLeadTime  float64 `json:"average_lead_time_hours"`
+}
+
+// IssueFilter is used to filter issue queries
+type IssueFilter struct {
+	Status    *Status
+	Priority  *int
+	IssueType *IssueType
+	Assignee  *string
+	Labels    []string
+	Limit     int
+}
+
+// WorkFilter is used to filter ready work queries
+type WorkFilter struct {
+	Status   Status
+	Priority *int
+	Assignee *string
+	Limit    int
+}