docs: update PROJECT.md, add README.md and CHANGELOG.md

- PROJECT.md updated to reflect v1.0 completion (10 phases, 39 plans,
  67 requirements). All key decisions marked as shipped.
- README.md: comprehensive project documentation with quick start,
  architecture, tech stack, configuration, and project structure.
- CHANGELOG.md: detailed changelog covering all 10 phases with
  feature descriptions organized by phase.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

CHANGELOG.md

@@ -0,0 +1,103 @@
+# Changelog
+
+All notable changes to Konstruct are documented in this file.
+
+## [1.0.0] - 2026-03-26
+
+### Phase 10: Agent Capabilities
+- Knowledge base ingestion pipeline — upload PDF, DOCX, PPTX, XLSX, CSV, TXT, Markdown; add URLs (Firecrawl scraping); add YouTube videos (transcript extraction)
+- Async document processing via Celery — chunk, embed (all-MiniLM-L6-v2), store in pgvector
+- KB management portal page with drag-and-drop upload, live status polling, delete, reindex
+- Google Calendar OAuth per tenant — list events, check availability, create events
+- Token auto-refresh with encrypted DB write-back
+- Web search connected to Brave Search API (platform-wide key)
+- Tool executor injects tenant_id/agent_id into all tool handlers
+- System prompt includes tool result formatting instruction (no raw JSON)
+
+### Phase 9: Testing & QA
+- Playwright E2E test suite — 29 tests across 7 critical flows (login, tenants, agent deploy, chat, RBAC, i18n, mobile)
+- Cross-browser testing — Chromium, Firefox, WebKit
+- Visual regression snapshots at 3 viewports (desktop, tablet, mobile)
+- axe-core accessibility scans on all pages
+- Lighthouse CI score gating (>= 80 hard floor)
+- Gitea Actions CI pipeline — backend lint + pytest → portal build + E2E + Lighthouse
+
+### Phase 8: Mobile + PWA
+- Responsive mobile layout with bottom tab bar (Dashboard, Employees, Chat, Usage, More)
+- Full-screen WhatsApp-style mobile chat with back arrow + agent name header
+- Visual Viewport API keyboard handling for iOS
+- PWA manifest with K monogram icons
+- Service worker (Serwist) with app shell + runtime caching
+- Web Push notifications (VAPID) with push subscription management
+- IndexedDB offline message queue with drain-on-reconnect
+- Smart install prompt on second visit
+- iOS safe-area support
+
+### Phase 7: Multilanguage
+- Full portal UI localization — English, Spanish, Portuguese
+- next-intl v4 (cookie-based locale, no URL routing)
+- Language switcher in sidebar (post-auth) and login page (pre-auth)
+- Browser locale auto-detection on first visit
+- Language preference saved to DB, synced to JWT
+- Agent templates translated in all 3 languages (JSONB translations column)
+- System prompt language instruction — agents auto-detect and respond in user's language
+- Localized invitation emails
+
+### Phase 6: Web Chat
+- Real-time WebSocket chat in the portal
+- Direct LLM streaming from WebSocket handler (bypasses Celery for speed)
+- Token-by-token streaming via NDJSON → Redis pub-sub → WebSocket
+- Conversation persistence (web_conversations + web_conversation_messages tables)
+- Agent picker dialog for new conversations
+- Markdown rendering (react-markdown + remark-gfm)
+- Typing indicator during LLM generation
+- All roles can chat (operators included)
+
+### Phase 5: Employee Design
+- Three-path AI employee creation: Templates / Guided Setup / Advanced
+- 6 pre-built agent templates (Customer Support Rep, Sales Assistant, Marketing Manager, Office Manager, Project Coordinator, Finance & Accounting Manager)
+- 5-step wizard (Role → Persona → Tools → Channels → Escalation)
+- System prompt auto-generation from wizard inputs
+- Templates stored as DB seed data with one-click deploy
+- Agent Designer as "Advanced" mode
+
+### Phase 4: RBAC
+- Three-tier roles: platform_admin, customer_admin, customer_operator
+- FastAPI RBAC guard dependencies (require_platform_admin, require_tenant_admin, require_tenant_member)
+- Email invitation flow with HMAC tokens (48-hour expiry, resend capability)
+- SMTP email sending via Python stdlib
+- Portal navigation and API endpoints enforce role-based access
+- Impersonation for platform admins with audit trail
+- Global user management page
+
+### Phase 3: Operator Experience
+- Slack OAuth "Add to Slack" flow with HMAC state protection
+- WhatsApp guided manual setup
+- 3-step onboarding wizard (Connect → Configure → Test)
+- Stripe subscription management (per-agent $49/month, 14-day trial)
+- BYO API key management with Fernet encryption + MultiFernet key rotation
+- Cost dashboard with Recharts (token usage, provider costs, message volume, budget alerts)
+- Agent-level cost tracking and budget limits
+
+### Phase 2: Agent Features
+- Two-layer conversational memory (Redis sliding window + pgvector HNSW)
+- Cross-conversation memory keyed per-user per-agent
+- Tool framework with 4 built-in tools (web search, KB search, HTTP request, calendar)
+- Schema-validated tool execution with confirmation flow for side-effecting actions
+- Immutable audit logging (REVOKE UPDATE/DELETE at DB level)
+- WhatsApp Business Cloud API adapter with Meta 2026 policy compliance
+- Two-tier business-function scoping (keyword allowlist + role-based LLM)
+- Human escalation with DM delivery, full transcript, and assistant mode
+- Cross-channel bidirectional media support with multimodal LLM interpretation
+
+### Phase 1: Foundation
+- Monorepo with uv workspaces
+- Docker Compose dev environment (PostgreSQL 16 + pgvector, Redis, Ollama)
+- PostgreSQL Row Level Security with FORCE ROW LEVEL SECURITY
+- Shared Pydantic models (KonstructMessage) and SQLAlchemy 2.0 async ORM
+- LiteLLM Router with Ollama + Anthropic/OpenAI and fallback routing
+- Celery orchestrator with sync-def pattern (asyncio.run)
+- Slack adapter (Events API) with typing indicator
+- Message Router with tenant resolution, rate limiting, idempotency
+- Next.js 16 admin portal with Auth.js v5, tenant CRUD, Agent Designer
+- Premium UI design system (indigo brand, dark sidebar, glass-morphism, DM Sans)