feat(nix): add UI-embedded flake package, refresh lock + docs

.gitignore

@@ -66,3 +66,7 @@ graph-ui/.npm-cache-local/
 # Python bytecode from tests/windows/ harness
 __pycache__/
 *.pyc
+
+# Nix build symlinks (nix build → ./result, ./result-1, …)
+/result
+/result-*

README.md

@@ -346,6 +346,38 @@ scripts/build.sh --with-ui          # with graph visualization
 # Binary at: build/c/codebase-memory-mcp
 ```
 
+### Nix (flake)
+
+The flake exposes two server packages plus the standalone frontend:
+
+| Package | Contents |
+|---------|----------|
+| `default` (`codebase-memory-mcp`) | Standard server, no UI |
+| `codebase-memory-mcp-ui` | Server with the graph UI embedded (`--ui=true` works) |
+| `graph-ui` | Just the built frontend assets (`dist/`) |
+
+Run directly without installing:
+
+```bash
+# Standard server
+nix run github:DeusData/codebase-memory-mcp
+
+# Server with the embedded graph UI
+nix run github:DeusData/codebase-memory-mcp#codebase-memory-mcp-ui -- --ui=true --port=9749
+# then open http://127.0.0.1:9749
+```
+
+Or build a binary into `./result/bin/codebase-memory-mcp`:
+
+```bash
+nix build github:DeusData/codebase-memory-mcp                          # standard
+nix build github:DeusData/codebase-memory-mcp#codebase-memory-mcp-ui   # with UI
+```
+
+Working in a clone? Use `.` in place of the flake URL, e.g. `nix run .#codebase-memory-mcp-ui -- --ui=true`, or drop into a shell that puts the binary on `PATH` with `nix shell .#codebase-memory-mcp-ui`.
+
+> **Note:** launched by hand (not from an MCP client) the server exits as soon as `stdin` closes — that's normal MCP behaviour. Keep `stdin` open while testing the UI, e.g. `sleep infinity | codebase-memory-mcp --ui=true --port=9749`. The `codebase-memory-mcp-ui` package embeds the UI at build time; `nix run`'ing the standard `default` package with `--ui=true` will refuse to start the HTTP server.
+
 ### Manual MCP Configuration
 
 <details>

flake.nix

@@ -9,10 +9,10 @@
       forAllSystems = f: nixpkgs.lib.genAttrs systems (system: f nixpkgs.legacyPackages.${system});
     in
     {
-      packages = forAllSystems (pkgs: {
+      packages = forAllSystems (pkgs: rec {
         default = pkgs.stdenv.mkDerivation {
           pname = "codebase-memory-mcp";
-          version = "0.6.0";
+          version = "0.9.0";
 
           src = ./.;
 
@@ -39,6 +39,56 @@
             platforms = systems;
           };
         };
+
+        # The graph-ui React frontend, built to static assets (graph-ui/dist).
+        # buildNpmPackage fetches npm deps offline via the pinned package-lock.json;
+        # bump npmDepsHash whenever that lockfile changes:
+        #   nix run nixpkgs#prefetch-npm-deps -- graph-ui/package-lock.json
+        graph-ui = pkgs.buildNpmPackage {
+          pname = "codebase-memory-graph-ui";
+          version = "0.1.0";
+
+          src = ./graph-ui;
+
+          npmDepsHash = "sha256-P1JVo+GFr+Gsq88dnn9OsedZqrTaj3DDGbej+nHbp4U=";
+
+          # `npm run build` runs `tsc -b && vite build`, emitting to dist/.
+          installPhase = ''
+            runHook preInstall
+            cp -r dist $out
+            runHook postInstall
+          '';
+        };
+
+        # Same server binary as `default`, but with the graph-ui assets embedded
+        # so `--ui=true` starts the HTTP server. The frontend is built separately
+        # by the graph-ui package above; here we drop its dist/ into place and run
+        # the embed + link path (cbm-with-ui) — no network access needed.
+        codebase-memory-mcp-ui = default.overrideAttrs (old: {
+          pname = "codebase-memory-mcp-ui";
+
+          buildPhase = ''
+            # cbm-with-ui depends on `embed`, which depends on `frontend`, which
+            # runs `npm ci && npm run build` — needs network access, unavailable
+            # in the sandbox. Supply the pre-built assets, run the embed script
+            # directly, then link with `cbm-with-ui` while telling make its
+            # `frontend`/`embed` prerequisites are already up to date (-o) so it
+            # won't re-run the npm build.
+            mkdir -p graph-ui/dist
+            cp -r ${graph-ui}/. graph-ui/dist/
+            chmod -R u+w graph-ui/dist
+
+            bash scripts/embed-frontend.sh graph-ui/dist build/c/embedded
+
+            make -j$NIX_BUILD_CORES -f Makefile.cbm \
+              -o frontend -o embed \
+              cbm-with-ui
+          '';
+
+          meta = old.meta // {
+            description = "codebase-memory-mcp with the embedded graph UI (--ui)";
+          };
+        });
       });
 
       devShells = forAllSystems (pkgs: {