feat: ACN Application Security Standard V7.30 compliance (19/23 items)

CRITICAL — Authentication & Access:
- TOTP MFA: otpauth-based, QR setup UI, sign-in flow integration,
  admin disable override, /account/security self-service page
- Session Timeouts: 8h absolute (maxAge), 30min idle (updateAge)
- Failed Auth Logging: Pino warn for invalid password/user/totp,
  info for successful login, audit entries for all auth events
- Concurrent Session Limit: ActiveSession model, oldest-kick strategy,
  max 3 per user (configurable in SystemSettings)

CRITICAL — HTTP Security:
- HSTS: max-age=31536000; includeSubDomains
- CSP: script/style/img/font/connect-src with Gemini/OpenAI whitelist
- X-XSS-Protection: 0 (CSP replaces legacy)
- Auth page cache: no-store, no-cache, must-revalidate
- Rate Limiting: 100/15min general API, 5/15min auth (Map-based)

Data Protection:
- XSS Sanitization: DOMPurify on comment bodies
- autocomplete="new-password" on all password/secret fields
- SameSite=Strict on all cookies (Credentials-only, no OAuth)
- File Upload Magic Bytes validation (PNG/JPEG/WebP/GIF/BMP/TIFF)

Logging & Monitoring:
- Login/Logout audit entries (Auth entityType)
- External API call logging with timing (OpenAI, Gemini)
- Input validation failure logging at warn level
- Concurrent session tracking in ActiveSession table

Documentation:
- docs/security-architecture.md (11 sections)
- docs/sdlc.md (CI pipeline, security gates, incident response)
- .gitea/PULL_REQUEST_TEMPLATE.md (security checklist)

Schema: User.totpSecret/totpEnabled, SystemSettings.sessionMaxAge/
sessionIdleTimeout/maxConcurrentSessions, ActiveSession model

Tests: 310 engine + 37 staffing pass. TypeScript clean.

Co-Authored-By: claude-flow <ruv@ruv.net>

packages/api/src/trpc.ts

@@ -3,6 +3,7 @@ import { resolvePermissions, PermissionKey, SystemRole } from "@capakraken/share
 import { initTRPC, TRPCError } from "@trpc/server";
 import { ZodError } from "zod";
 import { loggingMiddleware } from "./middleware/logging.js";
+import { apiRateLimiter } from "./middleware/rate-limit.js";
 
 // Minimal Session type to avoid next-auth peer-dep in this package
 interface Session {
@@ -100,6 +101,16 @@ export const protectedProcedure = t.procedure.use(withLogging).use(({ ctx, next
   if (!ctx.dbUser) {
     throw new TRPCError({ code: "UNAUTHORIZED", message: "User account not found" });
   }
+
+  // Rate limit by user ID
+  const rateLimitResult = apiRateLimiter(ctx.dbUser.id);
+  if (!rateLimitResult.allowed) {
+    throw new TRPCError({
+      code: "TOO_MANY_REQUESTS",
+      message: `Rate limit exceeded. Try again after ${rateLimitResult.resetAt.toISOString()}`,
+    });
+  }
+
   return next({
     ctx: {
       ...ctx,