feat: add Phase F.2 - The Biographer (memory agent)

Add The Biographer household member for user memory management:

Memory Service (direct access layer):
- src/core/memory_service.py for fast, LLM-free lookups
- Profile, preference, and fact management
- Session context with Redis caching
- Steward integration via prefetch_context()

The Biographer Agent:
- src/agents/biographer/ package with PydanticAI agent
- Discreet chronicler personality for privacy
- Tools: recall_semantic, list_memories, store_insight,
  update_profile, update_preference, forget_memory
- Registered with Household Registry on startup

Steward Integration:
- Memory context pre-fetch during analysis
- Profile/preferences included in Butler note
- Keyword-based context determination

Also includes:
- delegate_to_biographer() wrapper
- 34 new tests (capability + memory service)
- Version bump to 1.2.0

Documentation cleanup:
- Removed obsolete PHASE2_COMPLETE.md, PHASE2_PLAN.md
- Removed docs/library-desk-requirements.md
- Moved ORCHESTRATION_SCENARIOS.md to project root

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/agents/biographer/capability.py

@@ -0,0 +1,88 @@
+"""
+Biographer capability registration for the Household Registry.
+
+Defines The Biographer's capabilities and registers it as a
+household member for coordination by the Steward and Tatlock.
+"""
+from src.agents.biographer.agent import get_biographer_agent
+from src.agents.biographer.tools import BIOGRAPHER_TOOLS
+from src.core.household_registry import (
+    HouseholdCapability,
+    get_household_registry,
+)
+from src.core.logging_config import get_logger
+
+logger = get_logger(__name__)
+
+
+# The Biographer's capability summary for Steward coordination
+BIOGRAPHER_CAPABILITY = HouseholdCapability(
+    name="biographer",
+    role="The Biographer",
+    category="context",
+    description=(
+        "Memory keeper for the user's story: can RECALL personal facts "
+        "(car, job, family, pets), RECORD new information learned from "
+        "conversation, UPDATE profile (name, location, timezone) and "
+        "preferences (units, theme), and FORGET information when requested. "
+        "Use for: 'what car do I drive?', 'remember that I...', "
+        "'forget my...', 'what do you know about me?'"
+    ),
+    domains=[
+        "remember",
+        "recall",
+        "forget",
+        "memory",
+        "preferences",
+        "profile",
+        "personal",
+        "know",
+        "about me",
+        "my",
+    ],
+    cost="low",  # Mostly vector search, minimal LLM
+    requires_network=False,  # All local (Qdrant, Redis)
+)
+
+
+def get_biographer_capability() -> HouseholdCapability:
+    """Get The Biographer's capability definition."""
+    return BIOGRAPHER_CAPABILITY
+
+
+def register_biographer() -> None:
+    """
+    Register The Biographer with the Household Registry.
+
+    This makes The Biographer available for:
+    - Steward recommendations (via capability summary)
+    - Tatlock delegation (via agent reference)
+    - Tool scoping (via tool list)
+    """
+    registry = get_household_registry()
+
+    # Check if already registered
+    if "biographer" in registry:
+        logger.debug("biographer_already_registered")
+        return
+
+    registry.register(
+        name="biographer",
+        capability=BIOGRAPHER_CAPABILITY,
+        tools=BIOGRAPHER_TOOLS,
+        agent=get_biographer_agent(),
+    )
+
+    logger.info(
+        "biographer_registered",
+        role=BIOGRAPHER_CAPABILITY.role,
+        domains=BIOGRAPHER_CAPABILITY.domains,
+        tool_count=len(BIOGRAPHER_TOOLS),
+    )
+
+
+def unregister_biographer() -> None:
+    """Unregister The Biographer from the Household Registry."""
+    registry = get_household_registry()
+    registry.unregister("biographer")
+    logger.info("biographer_unregistered")