fix(snot): surface DB connection errors and clear stale error banner on search

snot/snot.html

@@ -351,6 +351,7 @@
         },
 
         async search() {
+            this.errorMessage = "";
             const response = await fetch("/search", {
                 method: "POST",
                 headers: { "Content-Type": "application/json" },

snot/snot.py

@@ -551,11 +551,14 @@ def fetch_videos(params: dict[str, str]) -> list[dict[str, Any]]:
     rows: list[dict[str, Any]] = []
     total: int | None = None
     while total is None or len(rows) < total:
+        try:
             response = client.get(
                 "/videos",
                 params={**params, "limit": "1000", "offset": str(len(rows))},
                 headers={"Prefer": "count=exact"} if total is None else None,
             )
+        except httpx.ConnectError as e:
+            raise RuntimeError(f"Cannot reach database at {client.base_url} ({e}). Is the server running and reachable?") from e
         response.raise_for_status()
         page = response.json()
         if total is None: