Flatten repo structure: move crawler/ to root, remove vqa/ and immoweb/

The crawler subdirectory was the only active project. Moving it to the
repo root simplifies paths and removes the unnecessary nesting. The
vqa/ and immoweb/ directories were legacy/unused and have been removed.

Updated .drone.yml, .gitignore, .claude/ docs, and skills to reflect
the new flat structure.

config/scraper_config.py

@@ -0,0 +1,89 @@
+"""Scraper configuration with environment variable loading."""
+from __future__ import annotations
+
+import os
+from dataclasses import dataclass
+from typing import Self
+
+
+@dataclass(frozen=True)
+class ScraperConfig:
+    """Configuration for the Rightmove scraper.
+
+    Attributes:
+        max_concurrent_requests: Maximum number of concurrent HTTP requests.
+        request_delay_ms: Delay between requests in milliseconds.
+        result_cap: Maximum results Rightmove returns per query (their limit).
+        split_threshold: When results exceed this, split the query further.
+        min_price_band: Minimum width of a price band (won't split below this).
+        max_pages_per_query: Maximum pages to fetch per subquery (60 * 25 = 1500).
+        proxy_url: Optional SOCKS proxy URL (e.g., socks5://localhost:9050 for Tor).
+        slow_response_threshold: Response time threshold in seconds for throttle detection.
+        enable_circuit_breaker: Whether to enable circuit breaker protection.
+        circuit_breaker_failure_threshold: Number of consecutive failures to open circuit.
+        circuit_breaker_recovery_timeout: Seconds to wait before testing recovery.
+    """
+
+    max_concurrent_requests: int = 5
+    request_delay_ms: int = 100
+    result_cap: int = 1500
+    split_threshold: int = 1200  # Split when approaching cap
+    min_price_band: int = 100  # Minimum band width in currency units
+    max_pages_per_query: int = 60  # 60 * 25 = 1500 results max
+    proxy_url: str | None = None
+    slow_response_threshold: float = 10.0  # seconds
+    enable_circuit_breaker: bool = True
+    circuit_breaker_failure_threshold: int = 5
+    circuit_breaker_recovery_timeout: float = 60.0
+
+    @classmethod
+    def from_env(cls) -> Self:
+        """Load configuration from environment variables.
+
+        Environment variables:
+            RIGHTMOVE_MAX_CONCURRENT: Max concurrent requests (default: 5)
+            RIGHTMOVE_REQUEST_DELAY_MS: Request delay in ms (default: 100)
+            RIGHTMOVE_RESULT_CAP: Result cap per query (default: 1500)
+            RIGHTMOVE_SPLIT_THRESHOLD: Split threshold (default: 1200)
+            RIGHTMOVE_MIN_PRICE_BAND: Minimum price band width (default: 100)
+            RIGHTMOVE_MAX_PAGES: Max pages per query (default: 60)
+            RIGHTMOVE_PROXY_URL: SOCKS proxy URL (default: None)
+            RIGHTMOVE_SLOW_RESPONSE_THRESHOLD: Slow response threshold in seconds (default: 10.0)
+            RIGHTMOVE_ENABLE_CIRCUIT_BREAKER: Enable circuit breaker (default: True)
+            RIGHTMOVE_CIRCUIT_BREAKER_FAILURES: Failures to open circuit (default: 5)
+            RIGHTMOVE_CIRCUIT_BREAKER_TIMEOUT: Recovery timeout in seconds (default: 60.0)
+
+        Returns:
+            ScraperConfig instance with values from environment or defaults.
+        """
+        return cls(
+            max_concurrent_requests=int(
+                os.environ.get("RIGHTMOVE_MAX_CONCURRENT", "5")
+            ),
+            request_delay_ms=int(
+                os.environ.get("RIGHTMOVE_REQUEST_DELAY_MS", "100")
+            ),
+            result_cap=int(os.environ.get("RIGHTMOVE_RESULT_CAP", "1500")),
+            split_threshold=int(
+                os.environ.get("RIGHTMOVE_SPLIT_THRESHOLD", "1200")
+            ),
+            min_price_band=int(
+                os.environ.get("RIGHTMOVE_MIN_PRICE_BAND", "100")
+            ),
+            max_pages_per_query=int(
+                os.environ.get("RIGHTMOVE_MAX_PAGES", "60")
+            ),
+            proxy_url=os.environ.get("RIGHTMOVE_PROXY_URL") or None,
+            slow_response_threshold=float(
+                os.environ.get("RIGHTMOVE_SLOW_RESPONSE_THRESHOLD", "10.0")
+            ),
+            enable_circuit_breaker=os.environ.get(
+                "RIGHTMOVE_ENABLE_CIRCUIT_BREAKER", "true"
+            ).lower() in ("true", "1", "yes"),
+            circuit_breaker_failure_threshold=int(
+                os.environ.get("RIGHTMOVE_CIRCUIT_BREAKER_FAILURES", "5")
+            ),
+            circuit_breaker_recovery_timeout=float(
+                os.environ.get("RIGHTMOVE_CIRCUIT_BREAKER_TIMEOUT", "60.0")
+            ),
+        )