get rid of file variant in CachedData

src/network/HttpClient.zig

@@ -2387,16 +2387,8 @@ pub const Transfer = struct {
     // Serve a cache entry as this transfer's response. Takes ownership of
     // `cached` (file-backed bodies are read into the arena and closed).
     fn bufferCached(self: *Transfer, cached: Cache.CachedResponse) !void {
-        const arena = self.arena;
-
         const body: []const u8 = switch (cached.data) {
             .buffer => |b| b,
-            .file => |f| blk: {
-                defer f.file.close(lp.io);
-                const buf = try arena.alloc(u8, f.len);
-                const n = try f.file.readPositionalAll(lp.io, buf, f.offset);
-                break :blk buf[0..n];
-            },
         };
 
         self.setResponseHead(cached.metadata.status, cached.metadata.content_type);

src/network/cache/Cache.zig

@@ -219,23 +219,16 @@ pub const RenewResponse = struct {
 
 pub const CachedData = union(enum) {
     buffer: []const u8,
-    file: struct {
-        file: std.Io.File,
-        offset: usize,
-        len: usize,
-    },
 
     pub fn deinit(self: CachedData) void {
         switch (self) {
             .buffer => {},
-            .file => |*f| f.file.close(lp.io),
         }
     }
 
     pub fn format(self: CachedData, writer: *std.Io.Writer) !void {
         switch (self) {
             .buffer => |buf| try writer.print("buffer({d} bytes)", .{buf.len}),
-            .file => |f| try writer.print("file(offset={d}, len={d} bytes)", .{ f.offset, f.len }),
         }
     }
 };