* fix(nix): enable sandboxed builds with bun2nix
The Nix package was broken on Linux because `bun install` requires
network access, which is blocked by Nix sandboxing (enabled by default
on Linux).
This switches to bun2nix for dependency management:
- Add bun2nix flake input to pre-fetch all npm dependencies
- Generate bun.nix lockfile for reproducible dependency resolution
- Copy bun cache to writable location during build to avoid EACCES
errors from bunx writing to the read-only Nix store
- Add nanoid as an explicit dependency (was imported directly but only
available as a transitive dep, which breaks with isolated linker)
- Update CI workflow to perform a full sandboxed build
- Add bun2nix to devShell for easy lockfile regeneration
Closes#197
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
* fix(nix): create writable workdir for database access
The app uses process.cwd()/data for the database path, but when running
from the Nix store the cwd is read-only. Create a writable working
directory with symlinks to app files and a real data directory.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>