feat: scaffold go backend foundation

.planning/REQUIREMENTS.md

@@ -8,13 +8,13 @@ interview-ready after each short practice loop.
 
 ### Backend and Workflow
 
-- [ ] **BACK-01**: Backend service is implemented in Go.
-- [ ] **BACK-02**: Backend exposes typed interfaces for tutor workflows.
-- [ ] **BACK-03**: Backend integrates internalized `agent-farm-go` workflow
+- [x] **BACK-01**: Backend service is implemented in Go.
+- [x] **BACK-02**: Backend exposes typed interfaces for tutor workflows.
+- [x] **BACK-03**: Backend integrates internalized `agent-farm-go` workflow
   patterns without ad hoc handler shellouts.
-- [ ] **BACK-04**: Workflow LLM execution uses `third-one` with configurable
+- [x] **BACK-04**: Workflow LLM execution uses `third-one` with configurable
   runtime and default `deepseek-v4-flash`.
-- [ ] **BACK-05**: Manually authored source files stay at or below 600 lines.
+- [x] **BACK-05**: Manually authored source files stay at or below 600 lines.
 
 ### Interview Practice
 
@@ -94,7 +94,7 @@ interview-ready after each short practice loop.
 
 | Requirement | Phase | Status |
 |-------------|-------|--------|
-| BACK-01..BACK-05 | Phase 1 | Pending |
+| BACK-01..BACK-05 | Phase 1 | Complete |
 | INT-01..INT-06 | Phase 2 | Pending |
 | MEM-01..MEM-05 | Phase 3 | Pending |
 | PROG-01..PROG-05 | Phase 4 | Pending |
@@ -108,4 +108,4 @@ interview-ready after each short practice loop.
 
 ---
 *Requirements defined: 2026-04-26*
-*Last updated: 2026-04-26 after Go backend direction was locked.*
+*Last updated: 2026-04-26 after Phase 1 execution.*

.planning/STATE.md

@@ -7,7 +7,7 @@ See: `.planning/PROJECT.md` (updated 2026-04-26)
 **Core value:** The user should feel and prove that they are becoming more
 interview-ready after each short practice loop.
 
-**Current focus:** Phase 1: Go Backend Foundation and Workflow Boundary.
+**Current focus:** Phase 2 planning: Diagnostic Interview Loop.
 
 ## Current Decisions
 
@@ -21,13 +21,15 @@ interview-ready after each short practice loop.
 - OpenSpec is the intent/requirements source of truth.
 - First interview track is Backend Developer Interview.
 - Phase 1 has context, research, and plan artifacts.
+- Phase 1 Go backend scaffold is implemented and verified.
 
 ## Next Actions
 
-1. Execute Phase 1 Go backend foundation plan.
+1. Plan Phase 2 diagnostic interview loop with GSD.
 2. Keep `docs/planning/WORKFLOW_CONTRACTS.md` aligned with Go structs during
-   implementation.
-3. After Phase 1, plan Phase 2 diagnostic interview loop.
+   future workflow implementation.
+3. Decide whether Phase 2 starts with in-memory diagnostic sessions or a small
+   persistence boundary.
 
 ## Validation Log
 
@@ -35,6 +37,9 @@ interview-ready after each short practice loop.
   before GSD planning docs were created.
 - 2026-04-26: First track, workflow contracts, and Phase 1 GSD plan were
   created.
+- 2026-04-26: Phase 1 implementation verified with `go test ./...`,
+  `openspec validate bootstrap-job-tutor-platform --strict`, and Go source
+  line-count check.
 
 ---
 *State initialized: 2026-04-26.*

.planning/phases/001-go-backend-foundation-and-workflow-boundary/001-SUMMARY.md

@@ -0,0 +1,55 @@
+# Phase 1 Summary
+
+**Status:** Complete
+**Completed:** 2026-04-26
+
+## Delivered
+
+- Initialized Go backend module.
+- Added `cmd/tutor-api` entrypoint.
+- Added app assembly package.
+- Added environment-backed config with defaults for:
+  - HTTP address
+  - environment
+  - workflow runtime path
+  - model key defaulting to `deepseek-v4-flash`
+  - third-one binary path
+- Added HTTP health endpoint at `GET /healthz`.
+- Added typed workflow boundary and stub runner.
+- Added tests for config, health endpoint, and workflow stub behavior.
+- Updated `AGENTS.md` with concrete Go validation commands.
+
+## Files Added
+
+- `go.mod`
+- `cmd/tutor-api/main.go`
+- `internal/app/server.go`
+- `internal/config/config.go`
+- `internal/config/config_test.go`
+- `internal/httpapi/handler.go`
+- `internal/httpapi/handler_test.go`
+- `internal/workflows/contracts.go`
+- `internal/workflows/runner.go`
+- `internal/workflows/runner_test.go`
+
+## Verification
+
+```powershell
+gofmt -w cmd internal
+go test ./...
+openspec validate bootstrap-job-tutor-platform --strict
+```
+
+All checks passed.
+
+Go source line-count check passed; no manually authored Go file exceeds 600
+lines.
+
+## Deferred
+
+- Real diagnostic interview workflow execution.
+- Persistence.
+- Auth.
+- Live third-one execution.
+- Frontend.
+- Ontology and asset generation.

.planning/phases/001-go-backend-foundation-and-workflow-boundary/001-VERIFICATION.md

@@ -0,0 +1,28 @@
+# Phase 1 Verification
+
+## Verdict
+
+PASS
+
+## Requirement Coverage
+
+- BACK-01: PASS. Go module and backend entrypoint exist.
+- BACK-02: PASS. `internal/workflows` exposes typed contracts and runner
+  interface.
+- BACK-03: PASS. HTTP handler receives a workflow runner dependency and does
+  not shell out.
+- BACK-04: PASS. Config includes workflow runtime, model key, and third-one
+  binary path. Default model key is `deepseek-v4-flash`.
+- BACK-05: PASS. Go source files are all under 600 lines.
+
+## Evidence
+
+- `go test ./...` passed.
+- `openspec validate bootstrap-job-tutor-platform --strict` passed.
+- Go line-count check passed.
+
+## Residual Risk
+
+The workflow runner is intentionally a stub. Real internalized `agent-farm-go`
+execution belongs to a later phase when diagnostic and grading behavior are
+implemented.