Switch Evotor integration to webhook-based token delivery flow

Replace OAuth 2.0 authorization code flow with Evotor's proprietary
webhook token delivery: POST /evotor/callback receives token server-to-server,
GET /evotor/link links it to the logged-in user's account.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

scripts/evotor-get-token.sh

@@ -0,0 +1,57 @@
+#!/usr/bin/env bash
+# Obtain an Evotor developer access token via password grant (no browser required).
+# Uses dev.evotor.ru credentials (your Evotor developer account).
+#
+# Usage: ./scripts/evotor-get-token.sh
+
+set -euo pipefail
+
+# Load .env if present
+if [[ -f .env ]]; then
+    set -a; source .env; set +a
+fi
+
+EVOTOR_TOKEN_URL="https://dev.evotor.ru/oauth/token"
+
+# Prompt for credentials
+read -rp "Evotor developer login (email): " EVOTOR_LOGIN
+read -rsp "Evotor developer password: " EVOTOR_PASSWORD
+echo
+
+echo
+echo "A 2FA code will be sent to your email if this IP is not recognized."
+read -rp "2FA code (leave blank if not required): " EVOTOR_2FA
+
+# Build request body
+BODY="type=LOGIN&grant_type=password&client_id=Evo-UI&username=$(python3 -c "import urllib.parse,sys; print(urllib.parse.quote(sys.argv[1]))" "$EVOTOR_LOGIN")&password=$(python3 -c "import urllib.parse,sys; print(urllib.parse.quote(sys.argv[1]))" "$EVOTOR_PASSWORD")"
+
+EXTRA_HEADERS=()
+if [[ -n "$EVOTOR_2FA" ]]; then
+    EXTRA_HEADERS+=(-H "2fa_confirmation: $EVOTOR_2FA")
+fi
+
+echo
+echo "Requesting token..."
+RESPONSE=$(curl -s -X POST "$EVOTOR_TOKEN_URL" \
+    -H "Content-Type: application/x-www-form-urlencoded" \
+    "${EXTRA_HEADERS[@]}" \
+    -d "$BODY")
+
+echo
+echo "Response:"
+echo "$RESPONSE" | python3 -m json.tool 2>/dev/null || echo "$RESPONSE"
+
+ACCESS_TOKEN=$(echo "$RESPONSE" | python3 -c "import sys,json; d=json.load(sys.stdin); print(d.get('access_token',''))" 2>/dev/null || true)
+
+if [[ -z "$ACCESS_TOKEN" ]]; then
+    echo
+    echo "ERROR: No access_token in response." >&2
+    exit 1
+fi
+
+echo
+echo "Access token:"
+echo "$ACCESS_TOKEN"
+echo
+echo "To save this token to .env, add or update:"
+echo "  EVOTOR_ACCESS_TOKEN=$ACCESS_TOKEN"