refactor: optimize token usage, deduplicate code, fix bugs across agents

Token reduction (~40% per session, ~2.3M fewer tokens per 200-feature project):
- Agent-type-specific tool lists: coding 9, testing 5, init 5 (was 19 for all)
- Right-sized max_turns: coding 300, testing 100 (was 1000 for all)
- Trimmed coding prompt template (~150 lines removed)
- Streamlined testing prompt with batch support
- YOLO mode now strips browser testing instructions from prompt
- Added Grep, WebFetch, WebSearch to expand project session

Performance improvements:
- Rate limit retries start at ~15s with jitter (was fixed 60s)
- Post-spawn delay reduced to 0.5s (was 2s)
- Orchestrator consolidated to 1 DB query per loop (was 5-7)
- Testing agents batch 3 features per session (was 1)
- Smart context compaction preserves critical state, discards noise

Bug fixes:
- Removed ghost feature_release_testing MCP tool (wasted tokens every test session)
- Forward all 9 Vertex AI env vars to chat sessions (was missing 3)
- Fix DetachedInstanceError risk in test batch ORM access
- Prevent duplicate testing of same features in parallel mode

Code deduplication:
- _get_project_path(): 9 copies -> 1 shared utility (project_helpers.py)
- validate_project_name(): 9 copies -> 2 variants in 1 file (validation.py)
- ROOT_DIR: 10 copies -> 1 definition (chat_constants.py)
- API_ENV_VARS: 4 copies -> 1 source of truth (env_constants.py)

Security hardening:
- Unified sensitive directory blocklist (14 dirs, was two divergent lists)
- Cached get_blocked_paths() for O(1) directory listing checks
- Terminal security warning when ALLOW_REMOTE=1 exposes WebSocket
- 20 new security tests for EXTRA_READ_PATHS blocking
- Extracted _validate_command_list() and _validate_pkill_processes() helpers

Type safety:
- 87 mypy errors -> 0 across 58 source files
- Installed types-PyYAML for proper yaml stub types
- Fixed SQLAlchemy Column[T] coercions across all routers

Dead code removed:
- 13 files deleted (~2,679 lines): unused UI components, debug logs, outdated docs
- 7 unused npm packages removed (Radix UI components with 0 imports)
- AgentAvatar.tsx reduced from 615 -> 119 lines (SVGs extracted to mascotData.tsx)

New CLI options:
- --testing-batch-size (1-5) for parallel mode test batching
- --testing-feature-ids for direct multi-feature testing

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

server/routers/assistant_chat.py

@@ -7,8 +7,6 @@ WebSocket and REST endpoints for the read-only project assistant.
 
 import json
 import logging
-import re
-from pathlib import Path
 from typing import Optional
 
 from fastapi import APIRouter, HTTPException, WebSocket, WebSocketDisconnect
@@ -27,30 +25,13 @@ from ..services.assistant_database import (
     get_conversation,
     get_conversations,
 )
+from ..utils.project_helpers import get_project_path as _get_project_path
+from ..utils.validation import is_valid_project_name as validate_project_name
 
 logger = logging.getLogger(__name__)
 
 router = APIRouter(prefix="/api/assistant", tags=["assistant-chat"])
 
-# Root directory
-ROOT_DIR = Path(__file__).parent.parent.parent
-
-
-def _get_project_path(project_name: str) -> Optional[Path]:
-    """Get project path from registry."""
-    import sys
-    root = Path(__file__).parent.parent.parent
-    if str(root) not in sys.path:
-        sys.path.insert(0, str(root))
-
-    from registry import get_project_path
-    return get_project_path(project_name)
-
-
-def validate_project_name(name: str) -> bool:
-    """Validate project name to prevent path traversal."""
-    return bool(re.match(r'^[a-zA-Z0-9_-]{1,50}$', name))
-
 
 # ============================================================================
 # Pydantic Models
@@ -145,9 +126,9 @@ async def create_project_conversation(project_name: str):
 
     conversation = create_conversation(project_dir, project_name)
     return ConversationSummary(
-        id=conversation.id,
-        project_name=conversation.project_name,
-        title=conversation.title,
+        id=int(conversation.id),
+        project_name=str(conversation.project_name),
+        title=str(conversation.title) if conversation.title else None,
         created_at=conversation.created_at.isoformat() if conversation.created_at else None,
         updated_at=conversation.updated_at.isoformat() if conversation.updated_at else None,
         message_count=0,