feat(cloudstore): record explicit prompt source attestations

internal/cloud/cloudstore/cloudstore.go

@@ -781,6 +781,16 @@ func (cs *CloudStore) migrate(ctx context.Context) error {
 			claimed_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
 			PRIMARY KEY (session_id, source_inbox_id)
 		)`,
+		`CREATE TABLE IF NOT EXISTS cloud_prompt_source_attestations (
+			id BIGINT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
+			session_id TEXT NOT NULL,
+			source_inbox_id TEXT NOT NULL,
+			sync_id TEXT NOT NULL,
+			owner_project TEXT NOT NULL,
+			prompt_project TEXT NOT NULL,
+			actor_id TEXT NOT NULL,
+			attested_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+		)`,
 		`CREATE TABLE IF NOT EXISTS cloud_project_sessions (
 			project_name TEXT NOT NULL,
 			session_id TEXT NOT NULL,

internal/cloud/cloudstore/prompt_source_attestation.go

@@ -0,0 +1,59 @@
+package cloudstore
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+)
+
+var ErrPromptSourceAttestationUnbound = errors.New("cloudstore: prompt source attestation requires exact session authority and prompt pair claim")
+
+// PromptSourceAttestation is an independent, append-only record of an explicit
+// human source assertion; it does not alter registration or claim audit history.
+type PromptSourceAttestation struct {
+	ID            int64
+	SessionID     string
+	SourceInboxID string
+	SyncID        string
+	OwnerProject  string
+	PromptProject string
+	ActorID       string
+	AttestedAt    time.Time
+}
+
+// AttestPromptSource records an already-authorized human assertion. Storage
+// does not check grants: the future authenticated server route must verify the
+// actor's current grants to both owner and prompt projects before calling it.
+func (cs *CloudStore) AttestPromptSource(ctx context.Context, sessionID, sourceInboxID, syncID, ownerProject, promptProject, actorID string) (*PromptSourceAttestation, error) {
+	if cs == nil || cs.db == nil {
+		return nil, fmt.Errorf("cloudstore: not initialized")
+	}
+	values := []*string{&sessionID, &sourceInboxID, &syncID, &ownerProject, &promptProject, &actorID}
+	for _, value := range values {
+		*value = strings.TrimSpace(*value)
+		if *value == "" {
+			return nil, fmt.Errorf("cloudstore: all attestation fields are required")
+		}
+	}
+	const query = `INSERT INTO cloud_prompt_source_attestations
+		(session_id, source_inbox_id, sync_id, owner_project, prompt_project, actor_id)
+		SELECT a.session_id, c.source_inbox_id, c.sync_id, a.owner_project, c.prompt_project, $6
+		FROM cloud_session_authority a
+		JOIN cloud_prompt_pair_claims c ON c.session_id = a.session_id
+		WHERE a.session_id = $1 AND c.source_inbox_id = $2 AND c.sync_id = $3
+		AND a.owner_project = $4 AND c.prompt_project = $5
+		RETURNING id, session_id, source_inbox_id, sync_id, owner_project, prompt_project, actor_id, attested_at`
+	var record PromptSourceAttestation
+	err := cs.db.QueryRowContext(ctx, query, sessionID, sourceInboxID, syncID, ownerProject, promptProject, actorID).
+		Scan(&record.ID, &record.SessionID, &record.SourceInboxID, &record.SyncID, &record.OwnerProject, &record.PromptProject, &record.ActorID, &record.AttestedAt)
+	if errors.Is(err, sql.ErrNoRows) {
+		return nil, ErrPromptSourceAttestationUnbound
+	}
+	if err != nil {
+		return nil, fmt.Errorf("cloudstore: attest prompt source: %w", err)
+	}
+	return &record, nil
+}

internal/cloud/cloudstore/prompt_source_attestation_test.go

@@ -0,0 +1,74 @@
+package cloudstore
+
+import (
+	"context"
+	"errors"
+	"testing"
+)
+
+func TestPromptSourceAttestationExactAuthorityAndAppendOnlyAudit(t *testing.T) {
+	cs := openIsolatedCloudStore(t)
+	ctx := context.Background()
+	if _, err := cs.db.ExecContext(ctx, `INSERT INTO cloud_project_sessions (project_name, session_id) VALUES ('owner', 'unregistered')`); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := cs.AttestPromptSource(ctx, "unregistered", "inbox", "sync", "owner", "prompt", "human"); !errors.Is(err, ErrPromptSourceAttestationUnbound) {
+		t.Fatalf("indexed session conferred authority: %v", err)
+	}
+	if err := cs.RegisterSessionAuthority(ctx, "session", "owner", "registrar"); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := cs.AttestPromptSource(ctx, "session", "inbox", "sync", "owner", "prompt", "human"); !errors.Is(err, ErrPromptSourceAttestationUnbound) {
+		t.Fatalf("unclaimed pair conferred authority: %v", err)
+	}
+	if err := cs.ClaimPromptPair(ctx, "session", "inbox", "sync", "prompt", "claimer"); err != nil {
+		t.Fatal(err)
+	}
+	before, err := cs.GetPromptPairClaim(ctx, "session", "inbox")
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, tc := range []struct {
+		name string
+		args [6]string
+	}{
+		{"wrong session", [6]string{"other", "inbox", "sync", "owner", "prompt", "human"}},
+		{"wrong inbox", [6]string{"session", "other", "sync", "owner", "prompt", "human"}},
+		{"wrong sync", [6]string{"session", "inbox", "other", "owner", "prompt", "human"}},
+		{"wrong owner", [6]string{"session", "inbox", "sync", "prompt", "prompt", "human"}},
+		{"wrong prompt", [6]string{"session", "inbox", "sync", "owner", "owner", "human"}},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			a := tc.args
+			if _, err := cs.AttestPromptSource(ctx, a[0], a[1], a[2], a[3], a[4], a[5]); !errors.Is(err, ErrPromptSourceAttestationUnbound) {
+				t.Fatalf("accepted mismatch: %v", err)
+			}
+		})
+	}
+	for i := 0; i < 6; i++ {
+		a := [6]string{"session", "inbox", "sync", "owner", "prompt", "human"}
+		a[i] = "  "
+		if _, err := cs.AttestPromptSource(ctx, a[0], a[1], a[2], a[3], a[4], a[5]); err == nil {
+			t.Fatalf("accepted blank field %d", i)
+		}
+	}
+	first, err := cs.AttestPromptSource(ctx, "session", "inbox", "sync", "owner", "prompt", "human-one")
+	if err != nil {
+		t.Fatal(err)
+	}
+	second, err := cs.AttestPromptSource(ctx, "session", "inbox", "sync", "owner", "prompt", "human-two")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if first.ID == second.ID || first.AttestedAt.IsZero() || second.AttestedAt.IsZero() || first.ActorID != "human-one" || second.ActorID != "human-two" {
+		t.Fatalf("audit records not independent: %+v %+v", first, second)
+	}
+	var count int
+	if err := cs.db.QueryRowContext(ctx, `SELECT COUNT(*) FROM cloud_prompt_source_attestations`).Scan(&count); err != nil || count != 2 {
+		t.Fatalf("count=%d err=%v", count, err)
+	}
+	after, err := cs.GetPromptPairClaim(ctx, "session", "inbox")
+	if err != nil || *before != *after {
+		t.Fatalf("claim audit changed: %+v %+v %v", before, after, err)
+	}
+}