mara on PR #775: "this is too much docs in code - move bigger picture
stuff to md files and put refs in code"
New `docs/gateway.md` consolidates the gateway architecture story
that was spreading across long inline comments in `hive-gateway.nix`,
`hive-matrix.nix`, and `hive-forge.nix`:
- vhost map (which URL serves what, which upstream, which option)
- matrix discovery flow (.well-known → sub-domain delegation
sequence)
- Accept-header SPA fallback pattern (#686 / #729 design history)
- local-dev `localHostsEntry` story
- sub-domain rationale (mara verdict tracking) + when sub-path is
right (hyperhive-internal apps)
- per-vhost tuning knobs (forge LFS, matrix long-poll, agent SSE)
- sequencing history (which PR added which routing piece)
In-code comments in the two nix modules get trimmed to short refs
into the doc — keeps the *why* in the markdown while the *what*
stays alongside the code:
- hive-gateway.nix: top-of-file comment, `agentPortsTable`,
`appendHttpConfig`, every location block + vhost
- hive-matrix.nix: `fluffychat-web-fixed`, `fluffychat-web-imaging`,
the dart compile postInstall
README.md gets a new row in the docs table pointing at gateway.md.
Verified `nix eval` still resolves the same vhost + location layout
after the comment trim — no behavioral change, just less in-code
prose.
