Make the component library a standalone product door (2.63.0).

Add /api/library datasheet import and component GET/PUT with no exam.
Reorganize pytest into datasheet, library, schematic, PCB, and AF+AI.
Document Rust criteria (none chosen; no rustup) and coding conformity.

tests/datasheet/test_deepseek_only.py

@@ -0,0 +1,54 @@
+"""Periscope LLM routing is DeepSeek only.
+
+Favor: every pipeline stage uses DeepSeek even if PROVIDER_* is set to
+anthropic; model_for_stage stays on deepseek-flash.
+Against: anthropic fallback is ignored; get_provider_by_name('anthropic')
+does not construct the Anthropic SDK client.
+"""
+
+from __future__ import annotations
+
+import pytest
+
+from backend.config import settings
+from backend.services.llm.factory import get_provider, get_provider_by_name
+
+
+@pytest.fixture
+def restore_routing():
+    snap = {
+        "provider_default": settings.provider_default,
+        "provider_validation": settings.provider_validation,
+        "fallback_provider_validation": settings.fallback_provider_validation,
+        "fallback_model_validation": settings.fallback_model_validation,
+        "deepseek_api_key": settings.deepseek_api_key,
+    }
+    if not settings.deepseek_api_key:
+        settings.deepseek_api_key = "sk-test-not-called"
+    yield
+    for k, v in snap.items():
+        setattr(settings, k, v)
+    get_provider_by_name.cache_clear()
+
+
+def test_stage_stays_deepseek_when_env_says_anthropic(restore_routing):
+    settings.provider_validation = "anthropic"
+    assert settings.provider_for_stage("validation") == "deepseek"
+    get_provider_by_name.cache_clear()
+    assert get_provider("validation").name == "deepseek"
+    assert "deepseek" in settings.model_for_stage("validation")
+
+
+def test_anthropic_fallback_is_not_used(restore_routing):
+    settings.fallback_provider_validation = "anthropic"
+    settings.fallback_model_validation = "claude-sonnet-4-6"
+    assert settings.fallback_for_stage("validation") is None
+
+
+def test_get_provider_by_name_does_not_load_anthropic(restore_routing):
+    get_provider_by_name.cache_clear()
+    try:
+        p = get_provider_by_name("anthropic")
+        assert p.name == "deepseek"
+    finally:
+        get_provider_by_name.cache_clear()