New Filter start to work

Changing how condition are handle to create a tree of condition to only
parse once.

So far the basic work, need more testing.

src/tokenizers/ziql.zig

@@ -72,11 +72,16 @@ pub const Token = struct {
 pub const Tokenizer = struct {
     buffer: [:0]const u8,
     index: usize,
+    last_token: Token = undefined,
 
     pub fn getTokenSlice(self: *Tokenizer, token: Token) []const u8 {
         return self.buffer[token.loc.start..token.loc.end];
     }
 
+    pub fn last(self: Tokenizer) Token {
+        return self.last_token;
+    }
+
     pub fn init(buffer: [:0]const u8) Tokenizer {
         // Skip the UTF-8 BOM if present.
         return .{
@@ -364,6 +369,7 @@ pub const Tokenizer = struct {
         }
 
         result.loc.end = self.index;
+        self.last_token = result;
         return result;
     }
 };