v2.0.3: Improve error handling, add tests, cleanup

- Fix bare except clauses in curator.py and main.py
- Change embedding model to snowflake-arctic-embed2
- Increase semantic_score_threshold to 0.6
- Add memory context explanation to systemprompt.md
- Add pytest dependencies to requirements.txt
- Remove unused context_handler.py and .env.example
- Add project documentation (CLAUDE.md) and test files

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

tests/test_config.py

@@ -0,0 +1,42 @@
+"""Tests for configuration."""
+import pytest
+from pathlib import Path
+from app.config import Config, EMBEDDING_DIMS
+
+
+class TestConfig:
+    """Tests for Config class."""
+
+    def test_default_values(self):
+        """Config should have sensible defaults."""
+        config = Config()
+        assert config.ollama_host == "http://10.0.0.10:11434"
+        assert config.qdrant_host == "http://10.0.0.22:6333"
+        assert config.qdrant_collection == "memories"
+        assert config.embedding_model == "snowflake-arctic-embed2"
+
+    def test_vector_size_property(self):
+        """Vector size should match embedding model."""
+        config = Config(embedding_model="snowflake-arctic-embed2")
+        assert config.vector_size == 1024
+
+    def test_vector_size_fallback(self):
+        """Unknown model should default to 1024."""
+        config = Config(embedding_model="unknown-model")
+        assert config.vector_size == 1024
+
+
+class TestEmbeddingDims:
+    """Tests for embedding dimensions mapping."""
+
+    def test_snowflake_arctic_embed2(self):
+        """snowflake-arctic-embed2 should have 1024 dimensions."""
+        assert EMBEDDING_DIMS["snowflake-arctic-embed2"] == 1024
+
+    def test_nomic_embed_text(self):
+        """nomic-embed-text should have 768 dimensions."""
+        assert EMBEDDING_DIMS["nomic-embed-text"] == 768
+
+    def test_mxbai_embed_large(self):
+        """mxbai-embed-large should have 1024 dimensions."""
+        assert EMBEDDING_DIMS["mxbai-embed-large"] == 1024