chore(openspec): drop 9 superseded proposals + 11 stub archive files

Drop 9 batch proposals that are superseded by the boocode-lift-analysis
(boocontext-audit, conductor upgrades, self-healing/verify-gate skills):
add-3tier-memory, import-llm-evaluator, import-pregel-engine, plugin-platform,
conductor-evolution, code-intelligence-upgrade, dev-workflow, ui-overhaul,
agent-reliability.

Delete 11 stub archive files (49-66B each, 'Status: Shipped. Archived.' only)
that provide zero documentation value over the existing CHANGELOG.md + git tags.

openspec/changes/archived/2026-06-07-memory-context-engineering/specs/long-term-memory/spec.md

@@ -0,0 +1,83 @@
+## ADDED Requirements
+
+### Requirement: Fact extraction from conversation
+The system SHALL extract structured facts from conversations using an LLM, with confidence scoring and category classification.
+
+#### Scenario: Extract facts from conversation turn
+- **WHEN** a conversation turn (user message + assistant reply) is processed
+- **THEN** the system SHALL call the configured LLM with the conversation text
+- **THEN** the LLM response SHALL be parsed as structured JSON with facts
+- **THEN** each fact SHALL contain: `content`, `category`, `confidence` (0.0-1.0)
+
+#### Scenario: Fact categories
+- **WHEN** a fact is extracted
+- **THEN** its `category` SHALL be one of: `preference`, `knowledge`, `context`, `behavior`, `goal`, `correction`
+- **THEN** the system SHALL validate the category against the allowed set
+
+#### Scenario: Confidence thresholds
+- **WHEN** a fact's confidence is below the configurable threshold (default 0.5)
+- **THEN** the fact SHALL NOT be persisted
+- **THEN** the system SHALL log that a low-confidence fact was skipped
+
+### Requirement: Fact CRUD operations
+The system SHALL support creating, reading, updating, and deleting memory facts.
+
+#### Scenario: Create fact
+- **WHEN** a new fact is created
+- **THEN** it SHALL be assigned a unique ID (`fact_{uuid_hex[:8]}`)
+- **THEN** it SHALL be timestamped with ISO-8601 UTC
+- **THEN** it SHALL be persisted to the core store
+
+#### Scenario: Delete fact by ID
+- **WHEN** a fact deletion is requested with a valid ID
+- **THEN** the fact SHALL be removed from the store
+- **THEN** the updated store SHALL be persisted
+
+#### Scenario: Delete non-existent fact
+- **WHEN** a fact deletion is requested with an unknown ID
+- **THEN** the system SHALL raise `KeyError`
+
+#### Scenario: Update fact
+- **WHEN** a fact update is requested with a valid ID
+- **THEN** the system SHALL update only the provided fields (`content`, `category`, `confidence`)
+- **THEN** the fact's `createdAt` SHALL NOT be modified
+- **THEN** the updated store SHALL be persisted
+
+### Requirement: Content deduplication
+The system SHALL prevent duplicate facts by casefolded content comparison.
+
+#### Scenario: Exact duplicate detected
+- **WHEN** a new fact's content (casefolded) matches an existing fact
+- **THEN** the new fact SHALL be skipped
+- **THEN** the existing fact SHALL remain unchanged
+- **THEN** the system SHALL log that a duplicate was skipped
+
+#### Scenario: Near-duplicate with different casing
+- **WHEN** a new fact's content differs only in letter casing
+- **THEN** it SHALL be treated as a duplicate
+- **THEN** the new fact SHALL be skipped
+
+### Requirement: Max facts limit
+The system SHALL enforce a configurable maximum number of stored facts (default 500).
+
+#### Scenario: Fact count exceeds limit
+- **WHEN** adding a new fact would exceed `max_facts`
+- **THEN** the system SHALL sort existing facts by confidence (descending)
+- **THEN** the lowest-confidence fact SHALL be removed
+- **THEN** the new fact SHALL be added
+
+### Requirement: Memory formatting for context injection
+The system SHALL format memory data into a compact string for injection into LLM system prompts, respecting a token budget.
+
+#### Scenario: Format with all sections
+- **WHEN** memory data contains user context, history, and facts
+- **THEN** the output SHALL include: "User Context:" with work/personal/topOfMind
+- **THEN** the output SHALL include: "History:" with recent/earlier/background
+- **THEN** the output SHALL include: "Facts:" sorted by confidence descending
+- **THEN** each fact SHALL be formatted as: `- [{category} | {confidence:.2f}] {content}`
+
+#### Scenario: Token budget enforcement
+- **WHEN** the formatted output exceeds `max_tokens` (default 2000)
+- **THEN** the system SHALL trim facts from lowest confidence up
+- **THEN** if still over budget, the output SHALL be truncated at the character level
+- **THEN** `"\n..."` SHALL be appended to indicate truncation