Adapt Pinscope to DeepSeek, auto datasheets, and a shared library.

Based on manvalan/pinscope main. Default LLM is DeepSeek with local
skills and PDF ingest. Datasheets are fetched from LCSC/TI, stored in
the component library, and review extracts abs-max with a deeper
checklist. Adds scripts/update-pinscope.sh for the production host.

tests/test_datasheet_finder.py

@@ -0,0 +1,121 @@
+"""Datasheet auto-finder: MPN matching, LCSC pick, TI slugs, routing."""
+
+from __future__ import annotations
+
+import asyncio
+
+from backend.services.datasheet_finder import (
+    DatasheetHit,
+    _pick_lcsc_product,
+    _ti_slugs,
+    find_datasheet,
+    mpn_matches,
+)
+
+
+def test_mpn_matches_exact_and_packing():
+    assert mpn_matches("CH340E", "CH340E")
+    assert mpn_matches("SPX3819M5-L-3-3", "SPX3819M5-L-3-3/TR")
+    assert mpn_matches("MSPM0G3507SPTR", "MSPM0G3507")
+    assert mpn_matches("MSPM0G3507", "MSPM0G3507SPTR")
+    # Variant letter is a different die — must not match
+    assert not mpn_matches("CH340", "CH340E")
+    assert not mpn_matches("CH340E", "CH340G")
+    assert not mpn_matches("TLV9062", "TLV9002")
+
+
+def test_pick_lcsc_prefers_exact_model():
+    products = [
+        {"productModel": "TPSPX3819M5-L-3-3", "pdfUrl": "http://a.pdf"},
+        {"productModel": "SPX3819M5-L-3-3", "pdfUrl": "http://b.pdf"},
+        {"productModel": "SPX3819M5-L-3-3/TR", "pdfUrl": "http://c.pdf"},
+    ]
+    picked = _pick_lcsc_product("SPX3819M5-L-3-3", products)
+    assert picked is not None
+    assert picked["pdfUrl"] == "http://b.pdf"
+
+
+def test_pick_lcsc_packing_fallback():
+    products = [
+        {"productModel": "CH340E/TR", "pdfUrl": "http://e.pdf"},
+    ]
+    picked = _pick_lcsc_product("CH340E", products)
+    assert picked is not None
+    assert picked["pdfUrl"] == "http://e.pdf"
+
+
+def test_pick_lcsc_rejects_unrelated():
+    products = [
+        {"productModel": "CH340G", "pdfUrl": "http://g.pdf"},
+        {"productModel": "USB3300", "pdfUrl": "http://u.pdf"},
+    ]
+    assert _pick_lcsc_product("CH340E", products) is None
+
+
+def test_ti_slugs_include_family():
+    slugs = _ti_slugs("MSPM0G3507SPTR")
+    assert slugs[0] == "mspm0g3507sptr"
+    assert "mspm0g3507" in slugs
+    # Must not clip "sptr" as if it were "...sp" + "tr".
+    assert "mspm0g3507sp" not in slugs
+    assert "mspm0g3507s" not in slugs
+
+
+def test_find_datasheet_uses_lcsc_then_skips_empty(monkeypatch):
+    async def fake_lcsc(mpn, lcsc_id=None):
+        return DatasheetHit(
+            mpn, pdf_bytes=b"%PDF-" + b"x" * 8000, url="https://datasheet.lcsc.com/x.pdf",
+            source="lcsc",
+        )
+
+    monkeypatch.setattr(
+        "backend.services.datasheet_finder._from_lcsc", fake_lcsc,
+    )
+
+    async def boom(mpn):
+        raise AssertionError("later sources should not run")
+
+    monkeypatch.setattr("backend.services.datasheet_finder._from_ti", boom)
+    monkeypatch.setattr("backend.services.datasheet_finder._from_digikey", boom)
+
+    hit = asyncio.run(find_datasheet("CH340E"))
+    assert hit.ok
+    assert hit.source == "lcsc"
+    assert hit.pdf_bytes.startswith(b"%PDF-")
+
+
+def test_find_datasheet_falls_through_to_ti(monkeypatch):
+    async def miss_lcsc(mpn, lcsc_id=None):
+        return None
+
+    async def hit_ti(mpn):
+        return DatasheetHit(
+            mpn, pdf_bytes=b"%PDF-" + b"t" * 8000,
+            url="https://www.ti.com/lit/ds/symlink/mspm0g3507.pdf",
+            source="ti",
+        )
+
+    monkeypatch.setattr("backend.services.datasheet_finder._from_lcsc", miss_lcsc)
+    monkeypatch.setattr("backend.services.datasheet_finder._from_ti", hit_ti)
+
+    async def boom(mpn):
+        raise AssertionError("digikey should not run")
+
+    monkeypatch.setattr("backend.services.datasheet_finder._from_digikey", boom)
+
+    hit = asyncio.run(find_datasheet("MSPM0G3507SPTR"))
+    assert hit.ok
+    assert hit.source == "ti"
+
+
+def test_find_datasheet_all_miss(monkeypatch):
+    async def miss(*args, **kwargs):
+        return None
+
+    monkeypatch.setattr("backend.services.datasheet_finder._from_lcsc", miss)
+    monkeypatch.setattr("backend.services.datasheet_finder._from_ti", miss)
+    monkeypatch.setattr("backend.services.datasheet_finder._from_digikey", miss)
+
+    hit = asyncio.run(find_datasheet("NOTAREALPART123"))
+    assert not hit.ok
+    assert "No datasheet found" in (hit.error or "")