feat: chat uploads, vision turn isolation, and MindSpace agent improvements

Add chat file/image upload UX, attachment proxying, vision thumbnails, and per-turn image scoping so agents only use the current upload. Extend MindSpace asset context, billing token state, OA/scenario verify scripts, and related runtime config.

Co-authored-by: Cursor <cursoragent@cursor.com>

billing-token-state.mjs

@@ -0,0 +1,79 @@
+import { normalizeTokenState } from './billing.mjs';
+
+export function loadCostEstimateConfig(env = process.env) {
+  const useBackendCost = env.H5_USE_BACKEND_COST === '1';
+  const enabled = useBackendCost && env.H5_COST_ESTIMATE_FROM_TOKENS !== '0';
+  const inputUsdPer1M = Number(env.H5_COST_ESTIMATE_INPUT_USD_PER_1M ?? 0.27);
+  const outputUsdPer1M = Number(env.H5_COST_ESTIMATE_OUTPUT_USD_PER_1M ?? 1.1);
+  return {
+    enabled,
+    inputUsdPer1M: Number.isFinite(inputUsdPer1M) && inputUsdPer1M >= 0 ? inputUsdPer1M : 0.27,
+    outputUsdPer1M: Number.isFinite(outputUsdPer1M) && outputUsdPer1M >= 0 ? outputUsdPer1M : 1.1,
+  };
+}
+
+export function pickSessionAccumulatedCost(session) {
+  if (!session || typeof session !== 'object') return null;
+  const raw = session.accumulatedCost ?? session.accumulated_cost ?? null;
+  if (raw == null) return null;
+  const value = Number(raw);
+  return Number.isFinite(value) && value >= 0 ? value : null;
+}
+
+export function estimateAccumulatedCostUsd(tokenStateRaw, estimateConfig = loadCostEstimateConfig()) {
+  if (!estimateConfig?.enabled) return null;
+  const state = normalizeTokenState(tokenStateRaw);
+  if (state.accumulatedInputTokens <= 0 && state.accumulatedOutputTokens <= 0) return null;
+  const inputUsd =
+    (state.accumulatedInputTokens * estimateConfig.inputUsdPer1M) / 1_000_000;
+  const outputUsd =
+    (state.accumulatedOutputTokens * estimateConfig.outputUsdPer1M) / 1_000_000;
+  const total = inputUsd + outputUsd;
+  return total > 0 ? total : null;
+}
+
+export function enrichTokenStateForBilling(
+  tokenStateRaw,
+  { sessionCost = null } = {},
+  env = process.env,
+) {
+  const state = normalizeTokenState(tokenStateRaw);
+  if (state.accumulatedCost != null && Number(state.accumulatedCost) >= 0) {
+    return state;
+  }
+
+  const sessionUsd = pickSessionAccumulatedCost(sessionCost);
+  if (sessionUsd != null) {
+    return { ...state, accumulatedCost: sessionUsd };
+  }
+
+  const estimatedUsd = estimateAccumulatedCostUsd(state, loadCostEstimateConfig(env));
+  if (estimatedUsd != null) {
+    return { ...state, accumulatedCost: estimatedUsd };
+  }
+
+  return state;
+}
+
+export async function resolveBillingTokenState(
+  tokenStateRaw,
+  { sessionId = null, fetchSession = null } = {},
+  env = process.env,
+) {
+  const state = normalizeTokenState(tokenStateRaw);
+  if (state.accumulatedCost != null && Number(state.accumulatedCost) >= 0) {
+    return state;
+  }
+
+  if (typeof fetchSession === 'function' && sessionId) {
+    try {
+      const session = await fetchSession(sessionId);
+      const enriched = enrichTokenStateForBilling(state, { sessionCost: session }, env);
+      if (enriched.accumulatedCost != null) return enriched;
+    } catch {
+      // Best-effort: fall through to token estimate.
+    }
+  }
+
+  return enrichTokenStateForBilling(state, {}, env);
+}