[IaC] Add Mnemosyne FEATURES.yaml — declarative feature manifest

Closes #1251

- Documents all shipped backend modules (archive, entry, ingest, linker, cli, tests)
- Documents all shipped frontend components (11 components)
- Lists planned/unshipped features (decay, pulse, embeddings, consolidation)
- References merged PRs for each feature
- Enforces canon_path: nexus/mnemosyne/

nexus/mnemosyne/FEATURES.yaml

@@ -0,0 +1,184 @@
+# ═══════════════════════════════════════════════════════════════
+# FEATURES.yaml — Mnemosyne Module Manifest
+# ═══════════════════════════════════════════════════════════════
+#
+# Single source of truth for what exists, what's planned, and
+# who owns what. Agents and humans MUST check this before
+# creating new PRs for Mnemosyne features.
+#
+# Statuses: shipped | in-progress | planned | deprecated
+# Canon path: nexus/mnemosyne/
+#
+# Parent epic: #1248 (IaC Workflow)
+# Created: 2026-04-12
+# ═══════════════════════════════════════════════════════════════
+
+project: mnemosyne
+canon_path: nexus/mnemosyne/
+description: The Living Holographic Archive — memory persistence, search, and graph analysis
+
+# ─── Backend Modules ───────────────────────────────────────
+modules:
+
+  archive:
+    status: shipped
+    files: [archive.py]
+    description: Core MnemosyneArchive class — CRUD, search, graph analysis
+    features:
+      - add / get / remove entries
+      - keyword search (substring match)
+      - semantic search (Jaccard + link-boost via HolographicLinker)
+      - linked entry traversal (BFS by depth)
+      - topic filtering and counts
+      - export (JSON/Markdown)
+      - graph data export (nodes + edges for 3D viz)
+      - graph clusters (connected components)
+      - hub entries (highest degree centrality)
+      - bridge entries (articulation points via DFS)
+      - tag management (add_tags, remove_tags, retag)
+      - entry update with content dedup (content_hash)
+      - find_duplicate (content hash matching)
+      - temporal queries (by_date_range, temporal_neighbors)
+      - rebuild_links (re-run linker across all entries)
+    merged_prs:
+      - "#1217"   # Phase 1 foundation
+      - "#1225"   # Semantic search
+      - "#1220"   # Export, deletion, richer stats
+      - "#1234"   # Graph clusters, hubs, bridges
+      - "#1238"   # Tag management
+      - "#1241"   # Entry update + content dedup
+      - "#1246"   # Temporal queries
+
+  entry:
+    status: shipped
+    files: [entry.py]
+    description: ArchiveEntry dataclass — id, title, content, topics, links, timestamps, content_hash
+
+  ingest:
+    status: shipped
+    files: [ingest.py]
+    description: Document ingestion pipeline — chunking, dedup, auto-linking
+
+  linker:
+    status: shipped
+    files: [linker.py]
+    description: HolographicLinker — Jaccard token similarity, auto-link discovery
+
+  cli:
+    status: shipped
+    files: [cli.py]
+    description: CLI interface — stats, search, ingest, link, topics, remove, export, clusters, hubs, bridges, rebuild, tag/untag/retag, timeline, neighbors
+
+  tests:
+    status: shipped
+    files:
+      - tests/__init__.py
+      - tests/test_archive.py
+      - tests/test_graph_clusters.py
+    description: Test suite covering archive CRUD, search, graph analysis, clusters
+
+# ─── Frontend Components ───────────────────────────────────
+# Located in nexus/components/ (shared with other Nexus features)
+
+frontend:
+
+  spatial_memory:
+    status: shipped
+    files: [nexus/components/spatial-memory.js]
+    description: 3D memory crystal rendering and spatial layout
+
+  memory_search:
+    status: shipped
+    files: [nexus/components/spatial-memory.js]
+    description: searchByContent() — text search through holographic archive
+    merged_prs:
+      - "#1201"  # Spatial search
+
+  memory_filter:
+    status: shipped
+    files: [] # inline in index.html
+    description: Toggle memory categories by region
+    merged_prs:
+      - "#1213"
+
+  memory_inspector:
+    status: shipped
+    files: [nexus/components/memory-inspect.js]
+    description: Click-to-inspect detail panel for memory crystals
+    merged_prs:
+      - "#1229"
+
+  memory_connections:
+    status: shipped
+    files: [nexus/components/memory-connections.js]
+    description: Browse, add, remove memory relationships panel
+    merged_prs:
+      - "#1247"
+
+  memory_birth:
+    status: shipped
+    files: [nexus/components/memory-birth.js]
+    description: Birth animation when new memories are created
+    merged_prs:
+      - "#1222"
+
+  memory_particles:
+    status: shipped
+    files: [nexus/components/memory-particles.js]
+    description: Ambient particle system — memory activity visualization
+    merged_prs:
+      - "#1205"
+
+  memory_optimizer:
+    status: shipped
+    files: [nexus/components/memory-optimizer.js]
+    description: Performance optimization for large memory sets
+
+  timeline_scrubber:
+    status: shipped
+    files: [nexus/components/timeline-scrubber.js]
+    description: Temporal navigation scrubber for memory timeline
+
+  health_dashboard:
+    status: shipped
+    files: [] # overlay in index.html
+    description: Archive statistics overlay panel
+    merged_prs:
+      - "#1211"
+
+# ─── Planned / Unshipped ──────────────────────────────────
+
+planned:
+
+  memory_decay:
+    status: planned
+    description: >
+      Memories have living energy that fades with neglect and
+      brightens with access. Vitality score based on access
+      frequency and recency. Was attempted in PR #1221 but
+      went stale — needs fresh implementation against current main.
+    priority: medium
+
+  memory_pulse:
+    status: planned
+    description: >
+      Visual pulse wave radiates through connection graph when
+      a crystal is clicked, illuminating linked memories by BFS
+      hop distance. Was attempted in PR #1226 — needs rebasing.
+    priority: medium
+
+  embedding_backend:
+    status: planned
+    description: >
+      Pluggable embedding backend for true semantic search
+      (replacing Jaccard token similarity). Support local models
+      via Ollama for sovereignty.
+    priority: high
+
+  memory_consolidation:
+    status: planned
+    description: >
+      Automatic merging of duplicate/near-duplicate memories
+      using content_hash and semantic similarity. Periodic
+      consolidation pass.
+    priority: low