Build me an interactive 3D knowledge galaxy from my markdown notes.

My notes folder is: [PASTE THE FULL PATH — or replace this line with: "I have no notes — generate 25 realistic sample notes about a small business into ./notes first"]

Requirements: — A Python 3 script (build.py, standard library only — no pip installs) that scans every .md file and writes viewer/graph-data.js containing const GRAPH = {nodes: [...], links: [...]}. Each node: a label from the filename, its folder as a group, and a ~700-character excerpt of the note text. Link two notes when one mentions the other's title or they share [[wikilinks]]. — A single-page viewer (viewer/index.html) using the 3d-force-graph library from a CDN — no npm, no build tools, no frameworks. — Make it CINEMATIC: black space background with a starfield, nodes glowing and color-coded by group, slow idle drift. Clicking a node flies the camera to it, highlights its neighbors, and opens a side panel showing that note's excerpt. — A tiny Python standard-library web server (server.py, port 4700) that serves ONLY the viewer/ folder. — IMPORTANT: give every node a numeric id equal to its position in the nodes array — later features depend on looking nodes up by index. — When done: start the server and tell me the URL to open in Chrome.

Checkpoint: você está olhando para o seu próprio conhecimento como uma galáxia. Navegue por ela. Só isso já vale uma gravação de tela.