Add testable task descriptions: T0.1 through T0.9

Each task includes:
- Scope: what to build
- Implementation: code sketches + details
- Verification: concrete test criteria
- Done criteria: acceptance checklist

tasks/T0.2.md

@@ -0,0 +1,108 @@
+# T0.2: Shared Types
+
+## Scope
+Implement `statemachine/types.go` with all config/input/output structs and document defaults.
+
+## Implementation
+File: `statemachine/types.go`
+
+```go
+type ModelSpec struct {
+    ModelID  string // e.g. "claude-opus-5", "claude-sonnet-5"
+    Thinking string // "adaptive" or ""
+    Effort   string // "low", "medium", "high", "xhigh", "max"
+}
+
+type PromptSpec struct {
+    TemplateRef string            // e.g. "planner/default.tmpl"
+    RawTemplate string            // overrides TemplateRef if non-empty
+    Variables   map[string]any
+    Model       ModelSpec
+    LessonsRef  string            // key into lessons store
+}
+
+type PiRetryPolicy struct {
+    ScheduleToCloseTimeout time.Duration // default: 5m
+    InitialInterval        time.Duration // default: 2s
+    MaximumInterval        time.Duration // default: 30s
+    BackoffCoefficient     float64       // default: 2.0
+    StreamTimeout          time.Duration // default: 30s
+    StreamTimeoutMax       time.Duration // default: 2m
+}
+
+type ActivityTuning struct {
+    ImplementerBaseTimeout time.Duration // default: 10m
+    ImplementerMaxRetries  int           // default: 3
+    JudgeTimeout           time.Duration // default: 5m
+    PiRetry                PiRetryPolicy
+}
+
+type OrchestratorConfig struct {
+    SystemPrompt string                    // shared prompt prefix
+    Skills       []SkillRef                // required skill sources
+    RolePrompts  map[string]PromptSpec     // per-role: "planner", "judge", "implementer"
+    Tuning       ActivityTuning
+}
+
+type OrchestratorInput struct {
+    TargetRepoPath string
+    RemoteURL      string
+    Milestone      string // e.g. "T0"
+    Config         OrchestratorConfig
+    DryRun         bool
+    CycleCount     int
+    MaxCyclesBeforeCAN int // default: 100
+}
+
+type OrchestratorOutput struct {
+    MilestoneComplete bool
+    Done              bool
+    LastError         string
+}
+
+type TaskUnitInput struct {
+    TaskID          string
+    TargetRepoPath  string
+    JudgeSpec       PromptSpec
+    ImplementerSpec PromptSpec
+    BaseTimeout     time.Duration
+    MaxJudgeRetries int
+}
+
+type TaskUnitOutput struct {
+    TaskID  string
+    Verdict string // "pass" or "fail"
+    Critique string
+    Branch  string
+}
+
+type SkillRef struct {
+    Name string // skill identifier
+    URL  string // source to clone
+}
+```
+
+## Verification
+```bash
+cd /Users/rockliang/workplace/Poimen/workflows
+go build ./statemachine/
+
+# Run unit test:
+go test -v ./tests -run TestTypesDefaults
+```
+
+Test file: `tests/types_test.go`
+```go
+func TestTypesDefaults(t *testing.T) {
+    // Verify all defaults are correctly set
+    pr := PiRetryPolicy{}
+    assert.Equal(t, 5*time.Minute, pr.ScheduleToCloseTimeout)
+    // ... more assertions
+}
+```
+
+## Done Criteria
+- `go build ./statemachine/` succeeds
+- `go test ./tests -run TestTypesDefaults` passes
+- All struct fields documented with default values
+- No compilation errors