Add Discord-native hybrid front-end for Jarvis (bot + bridge)

Transform isair/jarvis into a Discord-controlled voice assistant running on
the Ubuntu VNC desktop, keeping the mature ~39k-line Python brain intact.

- bot/ (Node + bun, discord.js): /자비스 slash commands (ephemeral),
  voice channel join + voice receive/playback, pluggable VNC screen broadcast
  (selfbot live / noVNC / screenshot)
- bridge/ (Python, Flask): wraps jarvis STT + run_reply_engine + Piper TTS
  behind a thin localhost HTTP API
- .env.example, scripts/ (start_bridge/start_bot/dev), README rewrite,
  docs/language-comparison.md and docs/vnc-xfce-setup.md

Language decision: hybrid (Python brain + Node/bun Discord layer) because
Discord blocks bot video; native screen broadcast only works via a Node
selfbot library.

tests/test_graph_memory_tools.py

@@ -0,0 +1,151 @@
+"""Tests for graph memory search methods: search_nodes and find_node_by_name.
+
+These methods on GraphMemoryStore support both the automatic enrichment
+(keyword search during reply) and the UI (name-based lookup).
+"""
+
+import pytest
+
+from src.jarvis.memory.graph import GraphMemoryStore
+
+
+# ── Fixtures ───────────────────────────────────────────────────────────
+
+
+@pytest.fixture
+def tmp_db(tmp_path):
+    """Return a path to a temporary database."""
+    return str(tmp_path / "test_search.db")
+
+
+@pytest.fixture
+def store(tmp_db):
+    """Return a fresh GraphMemoryStore."""
+    s = GraphMemoryStore(tmp_db)
+    yield s
+    s.close()
+
+
+@pytest.fixture
+def populated_store(store):
+    """Store with some pre-populated topic nodes."""
+    store.create_node(
+        name="Music Preferences",
+        description="What music the user enjoys",
+        data="Enjoys jazz and lo-fi hip hop. Favourite artist is Nujabes.",
+        parent_id="root",
+    )
+    store.create_node(
+        name="Work",
+        description="Information about the user's work life",
+        data="Works at Acme Corp as a senior engineer. Uses Python and TypeScript daily.",
+        parent_id="root",
+    )
+    store.create_node(
+        name="Health",
+        description="Health and fitness related memories",
+        data="Runs 3 times a week. Prefers dark roast coffee. Allergic to shellfish.",
+        parent_id="root",
+    )
+    return store
+
+
+# ── GraphMemoryStore.search_nodes ──────────────────────────────────────
+
+
+@pytest.mark.unit
+class TestSearchNodes:
+    """Tests for the keyword search method on GraphMemoryStore."""
+
+    def test_search_by_name(self, populated_store):
+        results = populated_store.search_nodes("Music")
+        assert len(results) == 1
+        assert results[0].name == "Music Preferences"
+
+    def test_search_by_data_content(self, populated_store):
+        results = populated_store.search_nodes("Nujabes")
+        assert len(results) == 1
+        assert "Nujabes" in results[0].data
+
+    def test_search_by_description(self, populated_store):
+        results = populated_store.search_nodes("fitness")
+        assert len(results) == 1
+        assert results[0].name == "Health"
+
+    def test_search_multiple_keywords(self, populated_store):
+        results = populated_store.search_nodes("Python engineer")
+        assert len(results) >= 1
+        assert results[0].name == "Work"
+
+    def test_search_no_results(self, populated_store):
+        results = populated_store.search_nodes("quantum physics")
+        assert results == []
+
+    def test_search_empty_query(self, populated_store):
+        results = populated_store.search_nodes("")
+        assert results == []
+
+    def test_search_whitespace_only(self, populated_store):
+        results = populated_store.search_nodes("   ")
+        assert results == []
+
+    def test_search_excludes_root(self, populated_store):
+        results = populated_store.search_nodes("Root")
+        assert all(r.id != "root" for r in results)
+
+    def test_search_respects_limit(self, populated_store):
+        results = populated_store.search_nodes("the user", limit=1)
+        assert len(results) <= 1
+
+    def test_search_touches_matched_nodes(self, populated_store):
+        node_before = populated_store.search_nodes("Music")[0]
+        initial_count = node_before.access_count
+        # Search again — the first search already touched it once
+        results = populated_store.search_nodes("Music")
+        refreshed = populated_store.get_node(results[0].id)
+        assert refreshed.access_count > initial_count
+
+    def test_search_ranks_by_relevance(self, populated_store):
+        """Nodes matching more keywords should rank higher."""
+        results = populated_store.search_nodes("dark roast coffee")
+        assert results[0].name == "Health"
+
+    def test_search_case_insensitive(self, populated_store):
+        results = populated_store.search_nodes("nujabes")
+        assert len(results) == 1
+        assert results[0].name == "Music Preferences"
+
+
+# ── GraphMemoryStore.find_node_by_name ─────────────────────────────────
+
+
+@pytest.mark.unit
+class TestFindNodeByName:
+    """Tests for exact name lookup."""
+
+    def test_find_existing_node(self, populated_store):
+        node = populated_store.find_node_by_name("Work")
+        assert node is not None
+        assert node.name == "Work"
+
+    def test_find_case_insensitive(self, populated_store):
+        node = populated_store.find_node_by_name("work")
+        assert node is not None
+        assert node.name == "Work"
+
+    def test_find_nonexistent(self, populated_store):
+        node = populated_store.find_node_by_name("Nonexistent Topic")
+        assert node is None
+
+    def test_find_excludes_root(self, store):
+        node = store.find_node_by_name("Root")
+        assert node is None
+
+    def test_find_with_parent_filter(self, populated_store):
+        node = populated_store.find_node_by_name("Work", parent_id="root")
+        assert node is not None
+        assert node.name == "Work"
+
+    def test_find_wrong_parent(self, populated_store):
+        node = populated_store.find_node_by_name("Work", parent_id="nonexistent")
+        assert node is None