Inject MCP server instructions into system prompt ...

- McpClient: collect instructions from MCP initialize handshake
- McpServerConfig: add 'instructions' field for Navi-side overlay
- McpManager.get_instructions(): merge server + config instructions
- ContextBuilder: new _mcp_context_msg() injects MCP server
  descriptions into every LLM context as a system message
- Agent passes mcp_manager to ContextBuilder
- mcp_servers.json: add overlay instructions for gnexus-book

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Propagate user profile to LLM context via current_user_info ContextVar ...

- Extend User model: username, first_name, last_name, phone, birth_date,
  country, city, locale (all from gnexus-auth profile)
- navi_users DDL: add new profile columns
- auth/deps + auth/callback: populate new fields on upsert
- /auth/me: return all profile fields
- Add current_user_info ContextVar for full user profile propagation
- websocket + messages: set current_user_info before agent.run()
- run_ephemeral: inherit and restore current_user_info
- ContextBuilder: _user_context_msg() injects [User context] with name,
  email, location, locale, role into LLM system messages
- _security_policy_msg: reads user_id/role from ContextVar directly

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Add multi-user sandbox: filesystem, terminal, code_exec, security policy ...

- filesystem, share_file: sandbox non-admin users to user_data/<user_id>/
- terminal: working_dir sandbox + allowlist + dangerous pattern block for users
- code_exec: sandbox CWD and temp files to user_data/<user_id>/ for users
- context_builder: inject dynamic security policy into LLM context (user/admin)
- config: terminal_user_allowed_commands setting
- agent: wire user_id/user_role through ContextBuilder.build()
- base: add current_user_role ContextVar; run_ephemeral inherits role

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Multi-user auth via gnexus-auth OAuth + hybrid role/permission model ...

- Integrate gnexus-auth-client-py (GAuthClient) for OAuth flow, token refresh,
  and webhook parsing
- Add navi/auth/ package: User model, Fernet encryptor, client singleton,
  deps (get_current_user, require_admin, require_permission)
- New tables: navi_users, user_auth_sessions (auto-created on startup)
- Session/memory isolation by user_id with legacy NULL support
- Cookie-based auth proxy: /auth/login, /callback, /logout, /me
- Webhook receiver /webhooks/gnexus-auth handling user events, global logout,
  session revocation, role/permission changes
- Admin endpoints (/admin/*) gated by role + permissions
- Webclient auth store with isAdmin/hasPermission guards
- Admin-only profile filtering in /agents/profiles
- 200/200 tests passing

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Improve 3D modeling validation prompts

Fix 3D modeling feedback: session context, CORS, and PNG workflow ...

- Embed session_id into the main system prompt so the model reliably
  sees the correct session files directory instead of hallucinating one.
- Add global CORS middleware to fix STL viewer iframe fetch errors.
- Switch modeler_3d PNG previews from content_publish to image_view
  so renders are debug-only for Navi, not user-facing cards.
- Remove literal {session_id} template from persona.txt.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Improve content publishing UX

Bootstrap test suite — Phase 1 unit tests ...

- docs/testing.md: testing strategy, mock strategy, phase breakdown
- tests/conftest.py: autouse fixture to reset navi.config.settings per test
- tests/conftest_factory.py: FakeLLMBackend, FakeTool, make_profile, make_registry helpers
- tests/unit/core/test_events.py: wire serialization for all 15 event dataclasses
- tests/unit/core/test_compressor.py: should_compress, partition_messages, format_for_summary, compress_context
- tests/unit/core/test_registry.py: ToolRegistry, ProfileRegistry, BackendRegistry
- tests/unit/core/test_context_builder.py: system prompt caching, persona injection, goal anchor, iteration budget
- tests/unit/profiles/test_base.py: Pydantic model coercion, defaults, extra fields
- navi/core/context_builder.py: use module-level `import navi.config` instead of `from navi.config import settings` so tests can swap the singleton

59 tests passing.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Extract PlanningEngine, ContextBuilder, ToolExecutor from agent.py ...

- navi/core/planning.py: new 3-phase planning pipeline (~390 lines)
- navi/core/context_builder.py: system prompt caching, memory/context injection, goal anchoring (~160 lines)
- navi/core/tool_executor.py: tool execution with middleware chain (~150 lines)
- navi/core/agent.py: reduced from ~1420 to ~770 lines; delegates to extracted classes

All compilation verified.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>