Initial import of LogDarioSeq baseline

Establishes version control for the personal Logseq DB fork before
starting the server-client architecture migration and domain features
described in docs/agent-guide and the approved implementation plan.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

cli/spec/domain/block.mli

@@ -0,0 +1,27 @@
+type position = First_child | Last_child | Sibling
+
+type t = {
+  id : Cli_primitive.db_id option;
+  uuid : Cli_primitive.uuid option;
+  title : string option;
+  name : string option;
+  order : int option;
+  parent : Selector.block option;
+  page : Selector.page option;
+  tags : Selector.tag Rrbvec.t;
+  properties : Property.assignment Rrbvec.t;
+  children : t Rrbvec.t;
+  raw : Melange_edn_melange.any;
+}
+
+type tree = { root : t }
+
+val position_of_string : string -> position option
+
+val make :
+  ?uuid:Cli_primitive.uuid -> ?title:string -> ?children:t Rrbvec.t -> unit -> t
+
+val of_value : Melange_edn_melange.any -> t
+val to_value : t -> Melange_edn_melange.map Melange_edn_melange.t
+val flatten : t Rrbvec.t -> t Rrbvec.t
+val label : t -> string option