fix(landscape): cast run status parameter so SetRunStatus type-checks in Postgres

The status parameter was used both as the assigned value (varchar column)
and in CASE comparisons against text literals, so Postgres deduced two
types for $2 and every run failed at SetRunStatus(running) with SQLSTATE
42P08; the failure also prevented marking the run failed, leaving it
queued. Cast every use to text.

Add TEST_DB_URL-gated repository tests (skipped without a database) that
exercise the landscape run/node SQL and the new dataset period/group
queries against a real Postgres, and document them in the README.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

internal/repository/postgres/landscape_db_test.go

@@ -0,0 +1,151 @@
+package postgres
+
+import (
+	"context"
+	"errors"
+	"os"
+	"testing"
+	"time"
+
+	"gis/internal/domain"
+
+	"github.com/google/uuid"
+	"github.com/jackc/pgx/v5/pgxpool"
+)
+
+// testPool connects to the database named by TEST_DB_URL (migrations already
+// applied) or skips the test. Repository SQL is otherwise only exercised by
+// hand, so these tests are the guard against Postgres-only failures such as
+// parameter type deduction (SQLSTATE 42P08) that no stub can reproduce.
+func testPool(t *testing.T) *pgxpool.Pool {
+	t.Helper()
+	url := os.Getenv("TEST_DB_URL")
+	if url == "" {
+		t.Skip("TEST_DB_URL not set; skipping database test")
+	}
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+	pool, err := Connect(ctx, url)
+	if err != nil {
+		t.Fatalf("connect: %v", err)
+	}
+	t.Cleanup(pool.Close)
+	return pool
+}
+
+func TestLandscapeRepository_SetRunStatus_AllTransitions(t *testing.T) {
+	pool := testPool(t)
+	repo := NewLandscapeRepository(pool)
+	ctx := context.Background()
+
+	run, err := repo.CreateRun(ctx, domain.LPRun{
+		Status: domain.LPRunQueued,
+		Params: []byte(`{}`),
+		Nodes:  []domain.LPRunNode{{NodeCode: "00", Stage: 0, Status: domain.LPNodePending}},
+	})
+	if err != nil {
+		t.Fatalf("CreateRun: %v", err)
+	}
+	t.Cleanup(func() { _, _ = pool.Exec(ctx, `DELETE FROM lp_runs WHERE id = $1`, run.ID) })
+
+	if err := repo.SetRunStatus(ctx, run.ID, domain.LPRunRunning, nil); err != nil {
+		t.Fatalf("SetRunStatus(running): %v", err)
+	}
+	got, err := repo.GetRun(ctx, run.ID)
+	if err != nil {
+		t.Fatalf("GetRun: %v", err)
+	}
+	if got.Status != domain.LPRunRunning || got.StartedAt == nil || got.FinishedAt != nil {
+		t.Fatalf("after running: status=%s started=%v finished=%v", got.Status, got.StartedAt, got.FinishedAt)
+	}
+
+	msg := "boom"
+	if err := repo.SetRunStatus(ctx, run.ID, domain.LPRunFailed, &msg); err != nil {
+		t.Fatalf("SetRunStatus(failed): %v", err)
+	}
+	got, err = repo.GetRun(ctx, run.ID)
+	if err != nil {
+		t.Fatalf("GetRun: %v", err)
+	}
+	if got.Status != domain.LPRunFailed || got.FinishedAt == nil || got.Error == nil || *got.Error != msg {
+		t.Fatalf("after failed: status=%s finished=%v error=%v", got.Status, got.FinishedAt, got.Error)
+	}
+
+	if err := repo.SetRunStatus(ctx, run.ID, domain.LPRunSucceeded, nil); err != nil {
+		t.Fatalf("SetRunStatus(succeeded): %v", err)
+	}
+}
+
+func TestLandscapeRepository_NodeLifecycleAndReuse(t *testing.T) {
+	pool := testPool(t)
+	repo := NewLandscapeRepository(pool)
+	ctx := context.Background()
+
+	newRun := func() domain.LPRun {
+		run, err := repo.CreateRun(ctx, domain.LPRun{
+			Status:    domain.LPRunQueued,
+			Params:    []byte(`{"window_size":2048}`),
+			Overrides: map[string]uuid.UUID{"lp-e": uuid.New()},
+			Nodes:     []domain.LPRunNode{{NodeCode: "00", Stage: 0, Status: domain.LPNodePending}},
+		})
+		if err != nil {
+			t.Fatalf("CreateRun: %v", err)
+		}
+		t.Cleanup(func() { _, _ = pool.Exec(ctx, `DELETE FROM lp_runs WHERE id = $1`, run.ID) })
+		return run
+	}
+
+	inputs := []domain.LPDatasetRef{{Group: "lp-z-wr", DatasetID: uuid.New()}}
+	outputs := []domain.LPDatasetRef{{Group: "lp-z-integrated", DatasetID: uuid.New()}}
+
+	first := newRun()
+	if err := repo.SetNodeStarted(ctx, first.ID, "00", "fp-1", inputs); err != nil {
+		t.Fatalf("SetNodeStarted: %v", err)
+	}
+	if err := repo.SetNodeFinished(ctx, first.ID, "00", domain.LPNodeSucceeded, outputs, nil); err != nil {
+		t.Fatalf("SetNodeFinished: %v", err)
+	}
+	got, err := repo.GetRun(ctx, first.ID)
+	if err != nil {
+		t.Fatalf("GetRun: %v", err)
+	}
+	if len(got.Nodes) != 1 || got.Nodes[0].Status != domain.LPNodeSucceeded ||
+		len(got.Nodes[0].Inputs) != 1 || got.Nodes[0].Inputs[0] != inputs[0] ||
+		len(got.Nodes[0].Outputs) != 1 || got.Nodes[0].Outputs[0] != outputs[0] ||
+		got.Nodes[0].StartedAt == nil || got.Nodes[0].FinishedAt == nil {
+		t.Fatalf("node row not round-tripped: %+v", got.Nodes)
+	}
+	if len(got.Overrides) != 1 {
+		t.Fatalf("overrides not round-tripped: %+v", got.Overrides)
+	}
+
+	second := newRun()
+	reused, err := repo.FindReusableOutputs(ctx, "00", "fp-1", second.ID)
+	if err != nil {
+		t.Fatalf("FindReusableOutputs: %v", err)
+	}
+	if len(reused) != 1 || reused[0] != outputs[0] {
+		t.Fatalf("reused = %+v, want %+v", reused, outputs)
+	}
+	if _, err := repo.FindReusableOutputs(ctx, "00", "fp-other", second.ID); !errors.Is(err, domain.ErrNotFound) {
+		t.Fatalf("unknown fingerprint: err = %v, want ErrNotFound", err)
+	}
+	if _, err := repo.FindReusableOutputs(ctx, "00", "fp-1", first.ID); !errors.Is(err, domain.ErrNotFound) {
+		t.Fatalf("own run must be excluded: err = %v, want ErrNotFound", err)
+	}
+
+	failMsg := "grid mismatch"
+	if err := repo.SetNodeFinished(ctx, second.ID, "00", domain.LPNodeFailed, nil, &failMsg); err != nil {
+		t.Fatalf("SetNodeFinished(failed): %v", err)
+	}
+	runs, err := repo.ListRuns(ctx, 10, 0)
+	if err != nil {
+		t.Fatalf("ListRuns: %v", err)
+	}
+	if len(runs) < 2 || runs[0].ID != second.ID {
+		t.Fatalf("ListRuns must be newest first: %+v", runs)
+	}
+	if n, err := repo.CountRuns(ctx); err != nil || n < 2 {
+		t.Fatalf("CountRuns = %d, %v", n, err)
+	}
+}