feat(recommendation-engine): S1 personalisering för 'Vad ska vi äta?'

- Mallbaserad proveniens i 12 språk (inga fria AI-texter i rekommendationer).
- memoryFit, tasteFit, cookingAssumptionFit endast vid personalization-samtycke.
- Hård grind i API:et: läser memory_items/taste_signals/cooking_assumption_profiles
  endast när userConsents.personalization = granted.
- NON_PERSONALIZED_WEIGHTS bevarar existerande beteende vid avsaknad av samtycke.
- Positiv, icke-restriktiv näringscopy (R7).
- Deterministisk scoring + enhetstester för S1.
- Integrationstest som verifierar provenans-gate med/utan samtycke.

packages/recommendation-engine/test/engine.test.ts

@@ -1,13 +1,19 @@
 import { describe, expect, it } from "vitest";
 import type { CoverageResult } from "@app/recipe-engine";
+import type { MemoryItem, TasteSignal } from "@app/shared-types";
 import {
+  containsForbiddenCopy,
+  DEFAULT_WEIGHTS,
   easterSunday,
   isEventActive,
   midsummerEve,
+  NON_PERSONALIZED_WEIGHTS,
   parseCraving,
   rankAll,
+  renderProvenance,
   scoreCandidate,
   seasonForDate,
+  type CookingAssumption,
   type RecommendationCandidate,
   type RecommendationContext,
 } from "../src/index.js";
@@ -52,6 +58,7 @@ const ctx: RecommendationContext = {
   favoriteCuisines: ["swedish"],
   remainingProteinG: 60,
   remainingKcal: 800,
+  personalizationEnabled: false,
 };
 
 describe("poängsättning (spec §18)", () => {
@@ -157,3 +164,168 @@ describe("säsongs- och eventmotor (spec §28)", () => {
     expect(isEventActive(jul, new Date("2026-08-02T00:00:00Z"))).toBe(false);
   });
 });
+
+describe("S1 personalisering", () => {
+  const memoryBase: MemoryItem = {
+    id: "m1",
+    userId: "u1",
+    kind: "structured_fact",
+    key: "favorite_cuisine_swedish",
+    summarySv: "Gillar svensk mat",
+    value: { favoriteCuisine: "swedish" },
+    origin: "user_stated",
+    confidence: 1,
+    verifiedByUser: true,
+    paused: false,
+    createdAt: new Date().toISOString(),
+    updatedAt: new Date().toISOString(),
+  };
+
+  const aiMemory: MemoryItem = {
+    ...memoryBase,
+    id: "m2",
+    origin: "ai_inferred",
+    confidence: 0.5,
+    verifiedByUser: false,
+    value: { favoriteCuisine: "swedish" },
+  };
+
+  const tastePositive: TasteSignal = {
+    id: "t1",
+    userId: "u1",
+    axis: "spice",
+    direction: 1,
+    strength: 0.8,
+    origin: "user_stated",
+    createdAt: new Date().toISOString(),
+  };
+
+  const tasteNegative: TasteSignal = {
+    ...tastePositive,
+    id: "t2",
+    direction: -1,
+  };
+
+  const cookingAssumption: CookingAssumption = {
+    canonicalIngredientId: "chicken",
+    averageEatenPortions: 4,
+    averageLeftoverPortions: 0.5,
+    observationCount: 5,
+  };
+
+  it("memoryFit boostar verified user_stated högre än ai_inferred", () => {
+    const verifiedCtx: RecommendationContext = {
+      ...ctx,
+      personalizationEnabled: true,
+      memoryItems: [memoryBase],
+      tasteSignals: [],
+      cookingAssumptions: [],
+    };
+    const aiCtx: RecommendationContext = {
+      ...ctx,
+      personalizationEnabled: true,
+      memoryItems: [aiMemory],
+      tasteSignals: [],
+      cookingAssumptions: [],
+    };
+    const verified = scoreCandidate(candidate({ cuisine: "swedish" }), verifiedCtx);
+    const ai = scoreCandidate(candidate({ cuisine: "swedish" }), aiCtx);
+    expect(verified.parts.memoryFit ?? 0).toBeGreaterThan(ai.parts.memoryFit ?? 0);
+  });
+
+  it("tasteFit ger positiv riktning för positiv signal", () => {
+    const spicyCandidate = candidate({ spiceLevel: 3 });
+    const positiveCtx: RecommendationContext = {
+      ...ctx,
+      personalizationEnabled: true,
+      memoryItems: [],
+      tasteSignals: [tastePositive],
+      cookingAssumptions: [],
+    };
+    const negativeCtx: RecommendationContext = {
+      ...ctx,
+      personalizationEnabled: true,
+      memoryItems: [],
+      tasteSignals: [tasteNegative],
+      cookingAssumptions: [],
+    };
+    const positive = scoreCandidate(spicyCandidate, positiveCtx);
+    const negative = scoreCandidate(spicyCandidate, negativeCtx);
+    expect(positive.parts.tasteFit ?? 0).toBeGreaterThan(negative.parts.tasteFit ?? 0);
+  });
+
+  it("cookingAssumptionFit boostar ingrediens som hushållet brukar äta upp", () => {
+    const ctxWithAssumption: RecommendationContext = {
+      ...ctx,
+      personalizationEnabled: true,
+      memoryItems: [],
+      tasteSignals: [],
+      cookingAssumptions: [cookingAssumption],
+    };
+    const boosted = scoreCandidate(
+      candidate({ ingredientIds: ["chicken", "onion"] }),
+      ctxWithAssumption,
+    );
+    const noMatch = scoreCandidate(
+      candidate({ ingredientIds: ["beef", "onion"] }),
+      ctxWithAssumption,
+    );
+    expect(boosted.parts.cookingAssumptionFit ?? 0).toBeGreaterThan(
+      noMatch.parts.cookingAssumptionFit ?? 0,
+    );
+  });
+
+  it("utan personalizationEnabled är personliga delpoäng noll", () => {
+    const noPersonalizationCtx: RecommendationContext = {
+      ...ctx,
+      personalizationEnabled: false,
+      memoryItems: [memoryBase],
+      tasteSignals: [tastePositive],
+      cookingAssumptions: [cookingAssumption],
+    };
+    const scored = scoreCandidate(
+      candidate({ cuisine: "swedish", spiceLevel: 3 }),
+      noPersonalizationCtx,
+    );
+    expect(scored.parts.memoryFit).toBe(0);
+    expect(scored.parts.tasteFit).toBe(0);
+    expect(scored.parts.cookingAssumptionFit).toBe(0);
+  });
+
+  it("proveniens renderas från mall med grundade fakta", () => {
+    const rendered = renderProvenance(
+      [{ key: "favoriteCuisine", args: { cuisine: "svensk" } }],
+      "sv-SE",
+    );
+    expect(rendered).toContain("svensk");
+    expect(rendered).toContain("berättat");
+  });
+
+  it("förbjuden copy upptäcks", () => {
+    expect(containsForbiddenCopy("Du har överskridit ditt kalorimål")).toBe(true);
+    expect(containsForbiddenCopy("Passar ditt proteinmål")).toBe(false);
+  });
+
+  it("scoring är deterministisk", () => {
+    const personalCtx: RecommendationContext = {
+      ...ctx,
+      personalizationEnabled: true,
+      memoryItems: [memoryBase],
+      tasteSignals: [tastePositive],
+      cookingAssumptions: [cookingAssumption],
+    };
+    const c = candidate({ ingredientIds: ["chicken"], spiceLevel: 3 });
+    const a = scoreCandidate(c, personalCtx);
+    const b = scoreCandidate(c, personalCtx);
+    expect(a.score).toBe(b.score);
+    expect(a.whySv).toBe(b.whySv);
+  });
+
+  it("icke-personaliserade vikter har noll för S1-komponenter", () => {
+    expect(NON_PERSONALIZED_WEIGHTS.memoryFit).toBe(0);
+    expect(NON_PERSONALIZED_WEIGHTS.tasteFit).toBe(0);
+    expect(NON_PERSONALIZED_WEIGHTS.cookingAssumptionFit).toBe(0);
+    // Befintliga vikter ska vara oförändrade.
+    expect(NON_PERSONALIZED_WEIGHTS.coverage).toBe(DEFAULT_WEIGHTS.coverage);
+  });
+});