recon: add /api/wiki-rewrite endpoint (extraction #5 prep, additive) (#9)

Per-tag HTTP wrapper over wiki_rewrite.rewrite_wiki_link so the (future)
navi-places service can rewrite OSM wiki tags to local Kiwix URLs over HTTP
instead of importing recon's wiki_rewrite module (which talks to Kiwix on
localhost:8430 and the wiki_cache table in /opt/recon/data/place_cache.db).
Companion to PR #8 (/api/wiki-enrich) — Matt picked option B (HTTP-couple the
Kiwix offline-wiki rewriting too, since it matters in prod).

  GET /api/wiki-rewrite?tag=<wikipedia|wikidata|wikivoyage|appropedia>&value=<raw>
  -> 200 {url, status}  where status is "local" | "public" | "original"
  -> 400 on missing value or unknown tag
  -> no 404 (unclassifiable value echoes back with status "original",
     mirroring rewrite_wiki_link)
  Public (no auth), like /api/place/* and /api/wiki-enrich.

Changes (additive only):
  - lib/wiki_rewrite_api.py: new wiki_rewrite_bp blueprint. Thin route directly
    over the existing rewrite_wiki_link(tag, value) — no extraction needed
    (it's already a clean standalone function, unlike wiki-enrich's lookup).
  - lib/api.py: register the blueprint (one block).
  - lib/wiki_rewrite_api_test.py: 5 tests (local Kiwix hit, public fallback,
    unclassifiable -> original, missing value -> 400, unknown tag -> 400),
    stubbing check_kiwix_has_article (no Kiwix/DB), plain-assert + __main__
    runner. Verified green against recon's venv (flask 3.1.2).

Does NOT touch place_detail's in-process _enrich_wiki_links — that gets removed
in a later PR once navi-places is live (same as PR #8). wiki_cache stays in
recon's own place_cache.db post-cutover (harmless positive-cache duplication).

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

lib/wiki_rewrite_api_test.py

@@ -0,0 +1,73 @@
+"""Tests for the /api/wiki-rewrite endpoint (extraction #5 prep).
+
+Plain-assert style (recon's venv has no pytest). Builds a minimal Flask app
+with only wiki_rewrite_bp registered. Mocks `wiki_rewrite.check_kiwix_has_article`
+to control the local-Kiwix-hit vs. fallback paths without touching Kiwix or the
+wiki_cache DB. classify_wiki_link (pure regex) runs for real. Run with pytest,
+or directly:  python -m lib.wiki_rewrite_api_test
+"""
+from flask import Flask
+
+from lib import wiki_rewrite
+from lib.wiki_rewrite_api import wiki_rewrite_bp
+
+
+def _client(kiwix_hit):
+    """kiwix_hit: (found_bool, url) returned by a stubbed check_kiwix_has_article."""
+    wiki_rewrite.check_kiwix_has_article = lambda source_type, article_id: kiwix_hit
+    app = Flask(__name__)
+    app.register_blueprint(wiki_rewrite_bp)
+    return app.test_client()
+
+
+def test_local_kiwix_hit():
+    url = "https://wiki.echo6.co/content/wikipedia/Filer,_Idaho"
+    c = _client((True, url))
+    resp = c.get("/api/wiki-rewrite?tag=wikipedia&value=Filer, Idaho")
+    assert resp.status_code == 200, resp.status_code
+    d = resp.get_json()
+    assert d["status"] == "local"
+    assert d["url"] == url
+
+
+def test_public_fallback_when_not_in_kiwix():
+    c = _client((False, None))  # not in Kiwix -> canonical public URL
+    resp = c.get("/api/wiki-rewrite?tag=wikipedia&value=Filer")
+    assert resp.status_code == 200, resp.status_code
+    d = resp.get_json()
+    assert d["status"] == "public"
+    assert d["url"] == "https://en.wikipedia.org/wiki/Filer"
+
+
+def test_unclassifiable_returns_original():
+    # 'wikidata' requires a Q-id; a non-matching value -> classify None -> original.
+    c = _client((False, None))
+    resp = c.get("/api/wiki-rewrite?tag=wikidata&value=not-a-qid")
+    assert resp.status_code == 200, resp.status_code
+    d = resp.get_json()
+    assert d["status"] == "original"
+    assert d["url"] == "not-a-qid"
+
+
+def test_missing_value_400():
+    c = _client((False, None))
+    assert c.get("/api/wiki-rewrite?tag=wikipedia").status_code == 400
+
+
+def test_unknown_tag_400():
+    c = _client((False, None))
+    assert c.get("/api/wiki-rewrite?tag=facebook&value=x").status_code == 400
+
+
+if __name__ == "__main__":
+    failures = 0
+    for _name, _fn in sorted(globals().items()):
+        if _name.startswith("test_") and callable(_fn):
+            try:
+                _fn()
+                print(f"PASS {_name}")
+            except Exception as exc:  # noqa: BLE001
+                failures += 1
+                print(f"FAIL {_name}: {exc!r}")
+    print("OK" if failures == 0 else f"{failures} FAILED")
+    raise SystemExit(1 if failures else 0)