feat(http): the HTTP layer on ClientHTTP1::Fetch and the typed socket error

Crafter.Network master now carries, in their final shape, the pieces the
HTTP layer and the SQL broker were written against on a side branch:
ClientHTTP1::Fetch follows redirects by RFC 9110 §15.4 on a URL type of
its own, and SocketErrorException is a std::system_error with the phase
that failed. The broker and the HTTP layer read the errno or the resolver
code from code() and the phase from the field, instead of matching
message prefixes, and the pin moves to that commit, so the build no
longer needs --local against a checkout of the side branch.

The messages the run log, the preflight detail and the SQL helper show
are unchanged, but for the wording of a refused URL.

AGENTS.md

@@ -106,7 +106,7 @@ Conventions:
   - An integer beyond 64 bits becomes a float.
 
   No file the drivers write holds these in practice, and a file that fails to parse is treated as a damaged one.
-- **HTTP.** `FetchHTTP1` ignores `*_proxy` variables. The OpenRouter requests send `User-Agent: crafter-review`; `app_ready` sends `review-gates`. Reason phrases are the standard ones, not the server's.
+- **HTTP.** `ClientHTTP1::Fetch` ignores `*_proxy` variables. The OpenRouter requests send `User-Agent: crafter-review`; `app_ready` sends `review-gates`. Reason phrases are the standard ones, not the server's.
 - **Seat placement** (SeatPool, Seats, Drivers):
   - An account whose 5-hour limit Anthropic has removed reports the weekly window alone. Its burst window (`Seats::BurstWindow`) is the weekly one: it is ranked and admitted by the weekly window with the passes in flight projected on it (0.04 points per pass at xhigh, 0.125 otherwise), under the 95 % cutoff.
   - Every OAuth account and the local login takes at most 128 passes at once, every driver's counted.