Release 0.13.0: cookie/privacy consent banner + policy pages (instrumentation prep)

Roadmap item #11. Ships the non-modal bottom-of-page cookie consent
banner, the default /privacy and /cookies policy pages, the
`cookie_consent` table + two §17 endpoints for server-side persistence,
the localStorage fallback for anonymous viewers, the /settings
"Privacy & cookies" tab for revisiting the choice, and the
`frontend/src/lib/consent.js` helper that roadmap item #13's analytics
SDK (v0.15.0) will gate against. No analytics SDK ships in this release
— the consent infrastructure goes in first so the gate is already in
place. Adds SPEC §14.5 / §14.6, lists two new endpoints in §17, names
the new table in §5, and surfaces four §19.2 candidates (content-repo
file vs env-var policy, GPC / DNT headers, i18n, item-#13 dependency).
Two new optional env vars (`VITE_PRIVACY_POLICY_URL`,
`VITE_COOKIES_POLICY_URL`) — defaults render the framework's stub
pages.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

backend/app/api_notifications.py

@@ -14,6 +14,8 @@ The endpoints in this module are:
   - `POST /api/users/me/quiet-hours`                       — set / clear
   - `POST /api/users/<id>/notification-mute`               — §15.8
   - `DELETE /api/users/<id>/notification-mute`             — §15.8
+  - `GET  /api/users/me/cookie-consent`                    — §14.5
+  - `PUT  /api/users/me/cookie-consent`                    — §14.5
   - `GET  /api/email/unsubscribe`                          — §15.4 one-click
   - `POST /api/webhooks/email-bounce`                      — §15.4 receiver
 
@@ -73,6 +75,15 @@ class BounceBody(BaseModel):
     kind: str = Field(default="hard")  # 'hard' or 'complaint'
 
 
+class CookieConsentBody(BaseModel):
+    # `essential` is always true at the surface; we accept it for symmetry
+    # but never persist a false value (the framework's strictly-necessary
+    # cookies are not user-optional per SPEC §14.5).
+    essential: bool = True
+    analytics: bool = False
+    other: bool = False
+
+
 # ---------------------------------------------------------------------------
 # Router
 # ---------------------------------------------------------------------------
@@ -362,6 +373,74 @@ def make_router(config: Config) -> APIRouter:
         )
         return {"ok": True}
 
+    # ----- Cookie consent (v0.13.0 / roadmap item #11; SPEC §14.5) -----
+    #
+    # The shape is intentionally small: three flags + a recorded-at stamp.
+    # The banner's local-vs-server precedence rule lives in the frontend
+    # (`consent.js`): on sign-in, the server row (if any) overrides local;
+    # otherwise local is uploaded.
+
+    @router.get("/api/users/me/cookie-consent")
+    async def get_cookie_consent(request: Request) -> dict[str, Any]:
+        viewer = auth.require_user(request)
+        row = db.conn().execute(
+            """
+            SELECT essential, analytics, other_cookies, recorded_at
+              FROM cookie_consent WHERE user_id = ?
+            """,
+            (viewer.user_id,),
+        ).fetchone()
+        if row is None:
+            return {
+                "essential": True,
+                "analytics": False,
+                "other": False,
+                "recorded_at": None,
+            }
+        return {
+            "essential": bool(row["essential"]),
+            "analytics": bool(row["analytics"]),
+            "other": bool(row["other_cookies"]),
+            "recorded_at": row["recorded_at"],
+        }
+
+    @router.put("/api/users/me/cookie-consent")
+    async def set_cookie_consent(body: CookieConsentBody, request: Request) -> dict[str, Any]:
+        viewer = auth.require_user(request)
+        # `essential` is the framework's strictly-necessary set; the
+        # surface accepts the flag for symmetry but never persists a
+        # false value. SPEC §14.5: a deployment that wants to make
+        # session-cookie storage optional must change the framework
+        # contract, not flip a flag here.
+        db.conn().execute(
+            """
+            INSERT INTO cookie_consent
+                   (user_id, essential, analytics, other_cookies, recorded_at)
+            VALUES (?, 1, ?, ?, datetime('now'))
+            ON CONFLICT(user_id) DO UPDATE SET
+                essential     = 1,
+                analytics     = excluded.analytics,
+                other_cookies = excluded.other_cookies,
+                recorded_at   = excluded.recorded_at
+            """,
+            (
+                viewer.user_id,
+                1 if body.analytics else 0,
+                1 if body.other else 0,
+            ),
+        )
+        row = db.conn().execute(
+            "SELECT recorded_at FROM cookie_consent WHERE user_id = ?",
+            (viewer.user_id,),
+        ).fetchone()
+        return {
+            "ok": True,
+            "essential": True,
+            "analytics": bool(body.analytics),
+            "other": bool(body.other),
+            "recorded_at": row["recorded_at"] if row else None,
+        }
+
     # ----- Email: one-click unsubscribe + bounce webhook -----
 
     @router.get("/api/email/unsubscribe")