feat(11-01): add five Drizzle table definitions for skill groups

- Add primaryKey import from drizzle-orm/sqlite-core
- Add skillGroups table with id, name, description, isBuiltin, timestamps
- Add skillGroupMembers junction table with composite PK (groupId, skillId)
- Add skillGroupInheritance table with composite PK (childGroupId, parentGroupId)
- Add agentSkillGroups table with composite PK (agentId, groupId)
- Add agentSkills table with composite PK (agentId, skillId)

server/src/services/skill-registry-schema.ts

@@ -1,4 +1,4 @@
-import { sqliteTable, text, integer, real } from "drizzle-orm/sqlite-core";
+import { sqliteTable, text, integer, real, primaryKey } from "drizzle-orm/sqlite-core";
 
 export const skills = sqliteTable("skills", {
   id: text("id").primaryKey(),
@@ -36,3 +36,43 @@ export const communityRatings = sqliteTable("community_ratings", {
   ratingCount: integer("rating_count"),
   source: text("source"),
 });
+
+export const skillGroups = sqliteTable("skill_groups", {
+  id: text("id").primaryKey(),
+  name: text("name").notNull(),
+  description: text("description"),
+  isBuiltin: integer("is_builtin").notNull().default(0),
+  createdAt: integer("created_at").notNull(),
+  updatedAt: integer("updated_at").notNull(),
+});
+
+export const skillGroupMembers = sqliteTable("skill_group_members", {
+  groupId: text("group_id").notNull(),
+  skillId: text("skill_id").notNull(),
+  addedAt: integer("added_at").notNull(),
+}, (t) => ({
+  pk: primaryKey({ columns: [t.groupId, t.skillId] }),
+}));
+
+export const skillGroupInheritance = sqliteTable("skill_group_inheritance", {
+  childGroupId: text("child_group_id").notNull(),
+  parentGroupId: text("parent_group_id").notNull(),
+}, (t) => ({
+  pk: primaryKey({ columns: [t.childGroupId, t.parentGroupId] }),
+}));
+
+export const agentSkillGroups = sqliteTable("agent_skill_groups", {
+  agentId: text("agent_id").notNull(),
+  groupId: text("group_id").notNull(),
+  assignedAt: integer("assigned_at").notNull(),
+}, (t) => ({
+  pk: primaryKey({ columns: [t.agentId, t.groupId] }),
+}));
+
+export const agentSkills = sqliteTable("agent_skills", {
+  agentId: text("agent_id").notNull(),
+  skillId: text("skill_id").notNull(),
+  installedAt: integer("installed_at").notNull(),
+}, (t) => ({
+  pk: primaryKey({ columns: [t.agentId, t.skillId] }),
+}));