feat: gate heavy solver JSON, field traceability API, GUI rod/export depth

- C: emit profiles/diagnostics/fourier only when enable flags are set; null otherwise
- API: fieldTraceability on case parse/default and solve; fix GET /solve/default options
- Tests: golden fingerprint, quality gates, C diagnostics invariants; cardQa mean empty guard
- Makefile: test-solver-sanitize ASan/UBSan target; README and COMPUTE_PLAN updates
- GUI: taper weight/MTS/guides/sinker round-trip, rod catalog, solver output toggles,
  results (profiles/diagnostics/Fourier/traceability), engineering checks and tabs
- Restore canonical WellName in base-case for regression; trace TaperGuidesCountArray

Made-with: Cursor

solver-api/tests/api.test.js

@@ -17,6 +17,10 @@ describe("solver-api", () => {
     expect(response.status).toBe(200);
     expect(response.body.runMetadata.source).toBe("base-case.xml");
     expect(response.body.solver.pointCount).toBe(200);
+    expect(response.body.solver.profiles).toBeNull();
+    expect(response.body.solver.diagnostics).toBeNull();
+    expect(response.body.fieldTraceability?.schemaVersion).toBe(2);
+    expect(Array.isArray(response.body.fieldTraceability?.fields)).toBe(true);
   });
 
   it("returns fea prototype result and comparison payload", async () => {
@@ -70,7 +74,7 @@ describe("solver-api", () => {
 
     expect(response.status).toBe(200);
     expect(response.body.solver.pointCount).toBe(200);
-    expect(response.body.parsed.model.wellName).toContain("191/01-27-007-09W2/00");
+    expect(response.body.parsed.model.wellName).toBe("PLACEHOLDER-WELL");
     expect(Array.isArray(response.body.parsed.unsupportedFields)).toBe(true);
   });
 
@@ -99,6 +103,7 @@ describe("solver-api", () => {
     expect(response.body.unsupportedFields.sort()).toEqual(
       defaultResp.body.unsupportedFields.sort()
     );
+    expect(response.body.fieldTraceability?.fields?.length).toBeGreaterThan(0);
   });
 
   it("rejects empty body on POST /case/parse", async () => {

solver-api/tests/quality.test.js

@@ -0,0 +1,44 @@
+import fs from "node:fs";
+import path from "node:path";
+import request from "supertest";
+import { describe, expect, it } from "vitest";
+import { buildApp } from "../src/app.js";
+
+const ROOT = path.resolve(path.dirname(new URL(import.meta.url).pathname), "../../");
+const xml = fs.readFileSync(path.join(ROOT, "data/cases/base-case.xml"), "utf-8");
+
+describe("quality gates", () => {
+  it("cross-model comparison has finite residuals when both solvers run", async () => {
+    const app = buildApp();
+    const response = await request(app).post("/solve").send({ xml, solverModel: "both" });
+    expect(response.status).toBe(200);
+    const rms = response.body.comparison.residualSummary.rms;
+    expect(Number.isFinite(rms)).toBe(true);
+    expect(rms).toBeGreaterThan(0);
+    expect(response.body.comparison.pointwiseResiduals.series.length).toBe(
+      response.body.comparison.pointwiseResiduals.points
+    );
+  });
+
+  it("perturbing rod friction changes peak polished load (field sensitivity)", async () => {
+    const app = buildApp();
+    const xmlHi = xml.replace(
+      "<RodFrictionCoefficient>0.2</RodFrictionCoefficient>",
+      "<RodFrictionCoefficient>0.28</RodFrictionCoefficient>"
+    );
+    const base = await request(app).post("/solve").send({ xml, solverModel: "fdm" });
+    const perturbed = await request(app).post("/solve").send({ xml: xmlHi, solverModel: "fdm" });
+    expect(base.status).toBe(200);
+    expect(perturbed.status).toBe(200);
+    expect(perturbed.body.solver.maxPolishedLoad).not.toBe(base.body.solver.maxPolishedLoad);
+  });
+
+  it("includes fieldTraceability on POST /solve", async () => {
+    const app = buildApp();
+    const response = await request(app).post("/solve").send({ xml });
+    expect(response.status).toBe(200);
+    expect(response.body.fieldTraceability?.schemaVersion).toBe(2);
+    const pumpDepth = response.body.fieldTraceability.fields.find((f) => f.xmlKey === "PumpDepth");
+    expect(pumpDepth?.category).toBe("physics");
+  });
+});