Memory unit and integration tests

[kovtcharov]

Summary

Comprehensive test suite for the memory system — unit tests for MemoryStore, integration tests for MemoryMixin lifecycle.

Spec: docs/spec/agent-memory-architecture.md → Implementation Order steps 4-5

Depends on: #542 (MemoryStore), #543 (MemoryMixin)

Unit Tests (tests/unit/test_memory_store.py)

MemoryStore Core

• Store and recall knowledge entries
• FTS5 search with AND/OR fallback
• Dedup: >80% word overlap in same category+context → updates
• Dedup: different contexts don't collide
• Confidence: +0.02 on recall, decay after 30 days
• Timestamps: ISO 8601 with timezone

Conversations

• Store and retrieve turns
• FTS5 search across conversations
• Time-based retrieval (get_recent_conversations)
• Context filtering

Tool History

• Log tool calls with timing
• Error filtering
• Per-tool stats (success rate, avg duration)

Temporal

• Store with due_at, retrieve via get_upcoming
• Overdue detection
• reminded_at lifecycle (remind → won't show → overdue resurfaces)
• Invalid date validation

Context / Sensitivity / Entity

• Context scoping filters correctly
• Sensitive items excluded from search by default
• Entity linking and get_by_entity

Dashboard Queries

• get_stats aggregation
• get_all_knowledge pagination and filtering
• get_tool_summary
• get_activity_timeline

Schema

• schema_version table created
• Migration path (future-proofing test)
• rebuild_fts recovery

Integration Tests (tests/integration/test_memory_mixin.py)

Lifecycle

• System prompt includes memory section
• System prompt cache invalidated per query
• Tool calls auto-logged to tool_history
• Memory tools excluded from tool_history
• Tool errors auto-stored as knowledge
• Conversation turns stored after process_query
• Heuristic extraction (preferences, facts)

Cross-Session

• Knowledge persists across agent restarts
• Conversation history persists
• Tool history persists
• Confidence decay on session start

Context

• System prompt filters by active context + global
• set_memory_context switches correctly
• Conversations tagged with active context

Acceptance Criteria

• All unit tests pass
• All integration tests pass
• No external dependencies (sqlite3 in-memory for tests)
• Tests run in CI (no hardware requirements)