feat(tools): implement CRUD operations for thoughts and projects

* Add tools for creating, retrieving, updating, and deleting thoughts.
* Implement project management tools for creating and listing projects.
* Introduce linking functionality between thoughts.
* Add search and recall capabilities for thoughts based on semantic queries.
* Implement statistics and summarization tools for thought analysis.
* Create database migrations for thoughts, projects, and links.
* Add helper functions for UUID parsing and project resolution.

migrations/004_create_thought_links.sql

@@ -0,0 +1,10 @@
+create table if not exists thought_links (
+  from_id uuid references thoughts(id) on delete cascade,
+  to_id uuid references thoughts(id) on delete cascade,
+  relation text not null,
+  created_at timestamptz default now(),
+  primary key (from_id, to_id, relation)
+);
+
+create index if not exists thought_links_from_idx on thought_links (from_id);
+create index if not exists thought_links_to_idx on thought_links (to_id);