Initial commit: ULPgrammer

- Core Telegram monitoring pipeline (scraper, processor, notifier, downloaders)
- Textual TUI frontend with thread-safe event bus
- SQLite persistence, severity scoring, dedup cache
- Fixed ULP parser: handles https:// truncation, port+path URLs, semicolon separator
- Test suite: 88 tests across scorer, cache, database, processor

utils/cache.py

@@ -0,0 +1,38 @@
+"""
+cache.py — Tracks already-processed file IDs to avoid redownloading.
+Persists to a simple JSON file on disk.
+"""
+
+import json
+import logging
+from pathlib import Path
+
+log = logging.getLogger(__name__)
+
+CACHE_FILE = Path("./data/cache.json")
+
+
+def _load() -> set:
+    if not CACHE_FILE.exists():
+        return set()
+    try:
+        with open(CACHE_FILE, "r") as f:
+            return set(json.load(f))
+    except Exception:
+        return set()
+
+
+def _save(seen: set) -> None:
+    with open(CACHE_FILE, "w") as f:
+        json.dump(list(seen), f)
+
+
+def is_seen(file_id: int) -> bool:
+    return file_id in _load()
+
+
+def mark_seen(file_id: int) -> None:
+    seen = _load()
+    seen.add(file_id)
+    _save(seen)
+    log.debug(f"  Cached file ID {file_id}")