feat: add spec definition api with versioning

migrations/sqlite/0000004_spec_definition.down.sql

@@ -0,0 +1 @@
+DROP TABLE spec_definitions;

migrations/sqlite/0000004_spec_definition.up.sql

@@ -0,0 +1,9 @@
+CREATE TABLE
+    spec_definitions (
+        name TEXT NOT NULL,
+        version TEXT NOT NULL,
+        schema TEXT NOT NULL,
+        created_at datetime NOT NULL,
+        updated_at datetime NOT NULL,
+        UNIQUE (name, version)
+    );

migrations/sqlite/0000005_spec_version.down.sql

@@ -0,0 +1,35 @@
+ALTER TABLE specs
+RENAME TO _specs;
+
+CREATE TABLE
+    specs (
+        id INTEGER PRIMARY KEY,
+        agent_id INTEGER,
+        tenant_id TEXT,
+        name TEXT NOT NULL,
+        revision INTEGER DEFAULT 0,
+        data TEXT,
+        created_at datetime NOT NULL,
+        updated_at datetime NOT NULL,
+        FOREIGN KEY (tenant_id) REFERENCES tenants (id),
+        FOREIGN KEY (agent_id) REFERENCES agents (id) ON DELETE CASCADE,
+        UNIQUE (agent_id, name) ON CONFLICT REPLACE
+    );
+
+INSERT INTO
+    specs
+SELECT
+    id,
+    agent_id,
+    tenant_id,
+    name,
+    revision,
+    data,
+    created_at,
+    updated_at
+FROM
+    _specs;
+
+DROP TABLE _specs;
+
+---

migrations/sqlite/0000005_spec_version.up.sql

@@ -0,0 +1,36 @@
+-- Add unique constraint on name/version to specs
+ALTER TABLE specs
+RENAME TO _specs;
+
+CREATE TABLE
+    specs (
+        id INTEGER PRIMARY KEY,
+        agent_id INTEGER,
+        tenant_id TEXT,
+        name TEXT NOT NULL,
+        version TEXT NOT NULL,
+        revision INTEGER DEFAULT 0,
+        data TEXT,
+        created_at datetime NOT NULL,
+        updated_at datetime NOT NULL,
+        FOREIGN KEY (tenant_id) REFERENCES tenants (id),
+        FOREIGN KEY (agent_id) REFERENCES agents (id) ON DELETE CASCADE,
+        UNIQUE (agent_id, name, version) ON CONFLICT REPLACE
+    );
+
+INSERT INTO
+    specs
+SELECT
+    id,
+    agent_id,
+    tenant_id,
+    name,
+    "0.0.0",
+    revision,
+    data,
+    created_at,
+    updated_at
+FROM
+    _specs;
+
+DROP TABLE _specs;