chore: drop non-code junk (pi-mono-reference, runtime state, root duplicates)

Remove files that should never have been tracked:

- pi-mono-reference/: 688-file copy of an upstream monorepo, zero imports,
  used only as offline human reference
- build/electron-builder.runtime.json: environment-specific build artifact
  with hardcoded local paths
- state/cancel-signal-state.json: runtime state written by the app
- prompt.txt, logo.svg (root): exact duplicates of the canonical copies
  under .planning/archive/ and assets/

Add state/ to .gitignore so future runtime state stays out.

pi-mono-reference/packages/pods/scripts/model_run.sh

@@ -1,83 +0,0 @@
-#!/usr/bin/env bash
-# Model runner script - runs sequentially, killed by pi stop
-set -euo pipefail
-
-# These values are replaced before upload by pi CLI
-MODEL_ID="{{MODEL_ID}}"
-NAME="{{NAME}}"
-PORT="{{PORT}}"
-VLLM_ARGS="{{VLLM_ARGS}}"
-
-# Trap to ensure cleanup on exit and kill any child processes
-cleanup() {
-    local exit_code=$?
-    echo "Model runner exiting with code $exit_code"
-    # Kill any child processes
-    pkill -P $$ 2>/dev/null || true
-    exit $exit_code
-}
-trap cleanup EXIT TERM INT
-
-# Force colored output even when not a TTY
-export FORCE_COLOR=1
-export PYTHONUNBUFFERED=1
-export TERM=xterm-256color
-export RICH_FORCE_TERMINAL=1
-export CLICOLOR_FORCE=1
-
-# Source virtual environment
-source /root/venv/bin/activate
-
-echo "========================================="
-echo "Model Run: $NAME"
-echo "Model ID: $MODEL_ID"
-echo "Port: $PORT"
-if [ -n "$VLLM_ARGS" ]; then
-    echo "vLLM Args: $VLLM_ARGS"
-fi
-echo "========================================="
-echo ""
-
-# Download model (with color progress bars)
-echo "Downloading model (will skip if cached)..."
-HF_HUB_ENABLE_HF_TRANSFER=1 hf download "$MODEL_ID"
-
-if [ $? -ne 0 ]; then
-    echo "❌ ERROR: Failed to download model" >&2
-    exit 1
-fi
-
-echo ""
-echo "✅ Model download complete"
-echo ""
-
-# Build vLLM command
-VLLM_CMD="vllm serve '$MODEL_ID' --port $PORT --api-key '$PI_API_KEY'"
-if [ -n "$VLLM_ARGS" ]; then
-    VLLM_CMD="$VLLM_CMD $VLLM_ARGS"
-fi
-
-echo "Starting vLLM server..."
-echo "Command: $VLLM_CMD"
-echo "========================================="
-echo ""
-
-# Run vLLM in background so we can monitor it
-echo "Starting vLLM process..."
-bash -c "$VLLM_CMD" &
-VLLM_PID=$!
-
-# Monitor the vLLM process
-echo "Monitoring vLLM process (PID: $VLLM_PID)..."
-wait $VLLM_PID
-VLLM_EXIT_CODE=$?
-
-if [ $VLLM_EXIT_CODE -ne 0 ]; then
-    echo "❌ ERROR: vLLM exited with code $VLLM_EXIT_CODE" >&2
-    # Make sure to exit the script command too
-    kill -TERM $$ 2>/dev/null || true
-    exit $VLLM_EXIT_CODE
-fi
-
-echo "✅ vLLM exited normally"
-exit 0