Dependabot was creating orphaned branches for risky major bumps
(Node 22->25, CUDA 12->13, Pillow 11->12, onnxruntime 1.20->1.25)
without opening PRs. These require manual evaluation, not auto-update.
Aligns pip and docker config with the npm ecosystem which already
ignores major bumps.
Add .vscode/ with Biome formatter, Tailwind, Vitest, Playwright, and
Python debug configs. Extract shared pnpm/Node setup into a composite
GitHub Action and add Dependabot and dependency-review workflows.