better logging on FsCache init failure

src/network/Network.zig

@@ -17,6 +17,7 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
+const log = @import("../log.zig");
 const builtin = @import("builtin");
 const net = std.net;
 const posix = std.posix;
@@ -29,7 +30,9 @@ const libcurl = @import("../sys/libcurl.zig");
 const http = @import("http.zig");
 const RobotStore = @import("Robots.zig").RobotStore;
 const WebBotAuth = @import("WebBotAuth.zig");
+
 const Cache = @import("cache/Cache.zig");
+const FsCache = @import("cache/FsCache.zig");
 
 const App = @import("../App.zig");
 const Network = @This();
@@ -238,7 +241,18 @@ pub fn init(allocator: Allocator, app: *App, config: *const Config) !Network {
         null;
 
     const cache = if (config.cacheDir()) |cache_dir_path|
-        Cache{ .kind = .{ .fs = try .init(cache_dir_path) } }
+        Cache{
+            .kind = .{
+                .fs = FsCache.init(cache_dir_path) catch |e| {
+                    log.err(.cache, "failed to init", .{
+                        .kind = "FsCache",
+                        .path = cache_dir_path,
+                        .err = e,
+                    });
+                    return e;
+                },
+            },
+        }
     else
         null;