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/001_enable_vector.sql

@@ -0,0 +1,2 @@
+create extension if not exists vector;
+create extension if not exists pgcrypto;

migrations/002_create_thoughts.sql

@@ -0,0 +1,17 @@
+create table if not exists thoughts (
+  id uuid default gen_random_uuid() primary key,
+  content text not null,
+  embedding vector(1536),
+  metadata jsonb default '{}'::jsonb,
+  created_at timestamptz default now(),
+  updated_at timestamptz default now()
+);
+
+create index if not exists thoughts_embedding_hnsw_idx
+  on thoughts using hnsw (embedding vector_cosine_ops);
+
+create index if not exists thoughts_metadata_gin_idx
+  on thoughts using gin (metadata);
+
+create index if not exists thoughts_created_at_idx
+  on thoughts (created_at desc);

migrations/003_add_projects.sql

@@ -0,0 +1,13 @@
+create table if not exists projects (
+  id uuid default gen_random_uuid() primary key,
+  name text not null unique,
+  description text,
+  created_at timestamptz default now(),
+  last_active_at timestamptz default now()
+);
+
+alter table thoughts add column if not exists project_id uuid references projects(id);
+alter table thoughts add column if not exists archived_at timestamptz;
+
+create index if not exists thoughts_project_id_idx on thoughts (project_id);
+create index if not exists thoughts_archived_at_idx on thoughts (archived_at);

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);

migrations/005_create_match_thoughts.sql

@@ -0,0 +1,31 @@
+create or replace function match_thoughts(
+  query_embedding vector(1536),
+  match_threshold float default 0.7,
+  match_count int default 10,
+  filter jsonb default '{}'::jsonb
+)
+returns table (
+  id uuid,
+  content text,
+  metadata jsonb,
+  similarity float,
+  created_at timestamptz
+)
+language plpgsql
+as $$
+begin
+  return query
+  select
+    t.id,
+    t.content,
+    t.metadata,
+    1 - (t.embedding <=> query_embedding) as similarity,
+    t.created_at
+  from thoughts t
+  where 1 - (t.embedding <=> query_embedding) > match_threshold
+    and t.archived_at is null
+    and (filter = '{}'::jsonb or t.metadata @> filter)
+  order by t.embedding <=> query_embedding
+  limit match_count;
+end;
+$$;

migrations/006_rls_and_grants.sql

@@ -0,0 +1,5 @@
+-- Grant these permissions to the database role used by the application.
+-- Replace amcs_user with the actual role in your deployment before applying.
+grant select, insert, update, delete on table public.thoughts to amcs_user;
+grant select, insert, update, delete on table public.projects to amcs_user;
+grant select, insert, update, delete on table public.thought_links to amcs_user;