feat: add canonical redirect, og_image, next_page_url, and sitemap caching across content routers

Implement canonical_redirect helper in content.py to enforce slug-based 301 redirects for gist, news, post, and project detail pages. Add first_image_url helper to extract primary image from item or attachments for Open Graph meta tags. Inject next_page_url into feed, gists, news, and projects list page SEO contexts for pagination link rel. Extend seo.py with SITEMAP_URL_LIMIT, SITEMAP_TTL constants and _sitemap cache variable for future sitemap generation optimization. Update profile page to raise 404 via not_found instead of 302 redirect, and include og_image from avatar_url.

tests/test_seo.py

@@ -213,3 +213,184 @@ def test_news_detail_has_newsarticle_schema(page, app_server):
     text = " ".join(scripts.nth(i).text_content() for i in range(scripts.count()))
     assert "NewsArticle" in text
     assert page.locator('meta[property="og:type"]').get_attribute("content") == "article"
+
+
+def _seed_owner():
+    from datetime import datetime, timezone
+    from uuid import uuid4
+    from devplacepy.database import get_table
+    uid = str(uuid4())
+    get_table("users").insert({
+        "uid": uid,
+        "username": f"seo_{uid[:8]}",
+        "email": f"{uid[:8]}@seo.test",
+        "password_hash": "x",
+        "role": "Member",
+        "is_active": True,
+        "created_at": datetime.now(timezone.utc).isoformat(),
+    })
+    return uid
+
+
+def _seed_post(image=None):
+    from datetime import datetime, timezone
+    from uuid import uuid4
+    from devplacepy.database import get_table
+    from devplacepy.utils import make_combined_slug
+    owner = _seed_owner()
+    uid = str(uuid4())
+    slug = make_combined_slug("SEO Detail Post", uid)
+    get_table("posts").insert({
+        "uid": uid, "user_uid": owner, "slug": slug,
+        "title": "SEO Detail Post", "content": "Body text for the SEO detail post.",
+        "topic": "general", "project_uid": None, "image": image,
+        "stars": 0, "created_at": datetime.now(timezone.utc).isoformat(),
+    })
+    return slug, uid
+
+
+def _seed_gist():
+    from datetime import datetime, timezone
+    from uuid import uuid4
+    from devplacepy.database import get_table
+    from devplacepy.utils import make_combined_slug
+    owner = _seed_owner()
+    uid = str(uuid4())
+    slug = make_combined_slug("SEO Detail Gist", uid)
+    get_table("gists").insert({
+        "uid": uid, "user_uid": owner, "slug": slug,
+        "title": "SEO Detail Gist", "description": "Gist description for SEO tests.",
+        "source_code": "print('seo')", "language": "python",
+        "stars": 0, "created_at": datetime.now(timezone.utc).isoformat(),
+    })
+    return slug, uid
+
+
+def _seed_project():
+    from datetime import datetime, timezone
+    from uuid import uuid4
+    from devplacepy.database import get_table
+    from devplacepy.utils import make_combined_slug
+    owner = _seed_owner()
+    uid = str(uuid4())
+    slug = make_combined_slug("SEO Detail Project", uid)
+    get_table("projects").insert({
+        "uid": uid, "user_uid": owner, "slug": slug,
+        "title": "SEO Detail Project", "description": "Project description for SEO tests.",
+        "project_type": "software", "platforms": "Linux", "status": "Released",
+        "stars": 0, "created_at": datetime.now(timezone.utc).isoformat(),
+    })
+    return slug, uid
+
+
+def _seed_news_image(news_uid):
+    from devplacepy.database import get_table
+    get_table("news_images").insert({
+        "news_uid": news_uid,
+        "url": "https://example.com/seo-news-image.jpg",
+    })
+
+
+def _seed_feed_posts(count):
+    from datetime import datetime, timezone, timedelta
+    from uuid import uuid4
+    from devplacepy.database import get_table
+    from devplacepy.utils import make_combined_slug
+    owner = _seed_owner()
+    topic = f"seopag{owner[:8]}"
+    base = datetime(2026, 1, 1, tzinfo=timezone.utc)
+    posts = get_table("posts")
+    for i in range(count):
+        uid = str(uuid4())
+        posts.insert({
+            "uid": uid, "user_uid": owner, "slug": make_combined_slug(f"seo pag {i}", uid),
+            "title": None, "content": f"seo pag post {i}", "topic": topic, "project_uid": None,
+            "image": None, "stars": 0,
+            "created_at": (base - timedelta(seconds=i)).isoformat(),
+        })
+    return topic
+
+
+def test_post_uid_redirects_to_canonical_slug(app_server):
+    slug, uid = _seed_post()
+    r = requests.get(f"{BASE_URL}/posts/{uid}", allow_redirects=False)
+    assert r.status_code == 301
+    assert r.headers["location"].endswith(f"/posts/{slug}"), r.headers.get("location")
+
+
+def test_post_slug_served_without_redirect(app_server):
+    slug, uid = _seed_post()
+    r = requests.get(f"{BASE_URL}/posts/{slug}", allow_redirects=False)
+    assert r.status_code == 200
+
+
+def test_gist_uid_redirects_to_canonical_slug(app_server):
+    slug, uid = _seed_gist()
+    r = requests.get(f"{BASE_URL}/gists/{uid}", allow_redirects=False)
+    assert r.status_code == 301
+    assert r.headers["location"].endswith(f"/gists/{slug}"), r.headers.get("location")
+
+
+def test_project_uid_redirects_to_canonical_slug(app_server):
+    slug, uid = _seed_project()
+    r = requests.get(f"{BASE_URL}/projects/{uid}", allow_redirects=False)
+    assert r.status_code == 301
+    assert r.headers["location"].endswith(f"/projects/{slug}"), r.headers.get("location")
+
+
+def test_news_uid_redirects_to_canonical_slug(app_server):
+    slug, uid = _seed_news()
+    r = requests.get(f"{BASE_URL}/news/{uid}", allow_redirects=False)
+    assert r.status_code == 301
+    assert r.headers["location"].endswith(f"/news/{slug}"), r.headers.get("location")
+
+
+def test_missing_profile_returns_404(app_server):
+    r = requests.get(f"{BASE_URL}/profile/no-such-user-xyz", allow_redirects=False)
+    assert r.status_code == 404
+
+
+def test_post_og_image_uses_content_image(page, app_server):
+    slug, _ = _seed_post(image="seo-content.png")
+    page.goto(f"{BASE_URL}/posts/{slug}", wait_until="domcontentloaded")
+    og = page.locator('meta[property="og:image"]').get_attribute("content")
+    assert og.endswith("/static/uploads/seo-content.png"), og
+
+
+def test_post_page_has_breadcrumb_schema(page, app_server):
+    slug, _ = _seed_post()
+    page.goto(f"{BASE_URL}/posts/{slug}", wait_until="domcontentloaded")
+    scripts = page.locator('script[type="application/ld+json"]')
+    text = " ".join(scripts.nth(i).text_content() for i in range(scripts.count()))
+    assert "BreadcrumbList" in text
+
+
+def test_post_schema_has_date_modified(page, app_server):
+    slug, _ = _seed_post()
+    page.goto(f"{BASE_URL}/posts/{slug}", wait_until="domcontentloaded")
+    scripts = page.locator('script[type="application/ld+json"]')
+    text = " ".join(scripts.nth(i).text_content() for i in range(scripts.count()))
+    assert "dateModified" in text
+
+
+def test_news_detail_image_has_alt_text(page, app_server):
+    slug, uid = _seed_news()
+    _seed_news_image(uid)
+    page.goto(f"{BASE_URL}/news/{slug}", wait_until="domcontentloaded")
+    alt = page.locator(".news-detail-image img").get_attribute("alt")
+    assert alt and alt.strip()
+
+
+def test_feed_pagination_emits_rel_next(page, app_server):
+    topic = _seed_feed_posts(26)
+    page.goto(f"{BASE_URL}/feed?topic={topic}", wait_until="domcontentloaded")
+    nxt = page.locator('link[rel="next"]')
+    assert nxt.count() == 1
+    href = nxt.get_attribute("href")
+    assert "before=" in href and f"topic={topic}" in href, href
+
+
+def test_post_detail_has_no_rel_next(page, app_server):
+    slug, _ = _seed_post()
+    page.goto(f"{BASE_URL}/posts/{slug}", wait_until="domcontentloaded")
+    assert page.locator('link[rel="next"]').count() == 0