Pass-through proxy with timeouts, size limits and a request log (closes #13)

The repo's first code, with the layout the prompts policies ask for:
Makefile, script/ entrypoints, a Dockerfile whose lint and test phases
gate the build, the Gitea workflow, the canonical dotfiles and
REPO_POLICIES.md. smallwebwaf passes each request to the app through
httputil.ReverseProxy within the four timeouts and two size limits,
works out the client's address behind trusted proxies, and writes one
JSON line per request. The tests run against real local servers.
SPEC.md now says what Go's HTTP server does before smallwebwaf sees a
request; make fmt only rewraps EVALUATION.md.

Model: opus-5-5

script/docker

@@ -0,0 +1,25 @@
+#!/bin/sh
+# script/docker: build the Docker image tagged with the project name.
+# Identical in all repos; the tag comes from script/projectname.
+# --no-cache because the gate phases the final stage depends on are RUN
+# steps, and a cached one is a check that did not run.
+set -eu
+
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd -P)"
+ROOT="$(cd "$SCRIPT_DIR/.." && pwd -P)"
+
+main() {
+    cd "$ROOT"
+    # Own line: a failing command substitution inside an argument does
+    # not trip `set -e`, so the inline form degrades silently to an
+    # empty constant. VERSION is computed here because .dockerignore
+    # excludes .git, so `git describe` in a build stage yields an empty
+    # version without failing.
+    version="$(git describe --tags --always --dirty 2>/dev/null || true)"
+    [ -n "$version" ] || version="unknown"
+    docker build --no-cache \
+        --build-arg VERSION="$version" \
+        -t "$("$SCRIPT_DIR/projectname")" .
+}
+
+main "$@"