feat(vector): add vector space identity helpers

tests/vector-space.mjs

@@ -0,0 +1,67 @@
+import assert from "node:assert/strict";
+
+import {
+  createVectorManifest,
+  deriveVectorSpace,
+  isVectorManifestCompatible,
+  normalizeVectorApiUrl,
+  summarizeVectorSpaceChange,
+} from "../vector/vector-space.js";
+
+assert.equal(
+  normalizeVectorApiUrl("https://example.com/v1/embeddings?key=secret"),
+  "https://example.com/v1",
+);
+
+const baseConfig = {
+  mode: "direct",
+  apiUrl: "https://example.com/v1/embeddings",
+  apiKey: "sk-should-not-appear",
+  model: "text-embedding-3-small",
+};
+
+const space1536 = deriveVectorSpace(baseConfig, 1536, { probedAt: 1 });
+const sameSpace = deriveVectorSpace(
+  { ...baseConfig, apiKey: "sk-different" },
+  1536,
+  { probedAt: 2 },
+);
+assert.equal(space1536.vectorSpaceId, sameSpace.vectorSpaceId);
+assert.equal(JSON.stringify(space1536).includes("sk-should-not-appear"), false);
+assert.equal(space1536.observedDim, 1536);
+
+const space3072 = deriveVectorSpace(baseConfig, 3072, { probedAt: 3 });
+assert.notEqual(space1536.vectorSpaceId, space3072.vectorSpaceId);
+assert.equal(summarizeVectorSpaceChange(space1536, space3072), "dimension-changed");
+
+const differentModel = deriveVectorSpace(
+  { ...baseConfig, model: "text-embedding-3-large" },
+  1536,
+  { probedAt: 4 },
+);
+assert.notEqual(space1536.vectorSpaceId, differentModel.vectorSpaceId);
+assert.equal(summarizeVectorSpaceChange(space1536, differentModel), "model-changed");
+
+const differentEndpoint = deriveVectorSpace(
+  { ...baseConfig, apiUrl: "https://other.example.com/v1/embeddings" },
+  1536,
+  { probedAt: 5 },
+);
+assert.notEqual(space1536.vectorSpaceId, differentEndpoint.vectorSpaceId);
+assert.equal(summarizeVectorSpaceChange(space1536, differentEndpoint), "endpoint-changed");
+
+const manifest = createVectorManifest({
+  backend: "local",
+  vectorSpace: space1536,
+  status: "clean",
+  nodeCount: 2,
+  embeddedNodeCount: 2,
+});
+assert.equal(isVectorManifestCompatible(manifest, space1536), true);
+assert.equal(isVectorManifestCompatible(manifest, space3072), false);
+assert.equal(
+  isVectorManifestCompatible({ ...manifest, status: "stale" }, space1536),
+  false,
+);
+
+console.log("vector-space tests passed");