Re-vendor the canonical files from sneak/prompts at dd4027b (closes #112)

The shared files are fetched from sneak/prompts dd4027b, with this
repository's own entries after the shared content in .gitignore,
.editorconfig and .dockerignore.

Lint and tests are Dockerfile phases (golangci-lint v2.14.0, Debian Go
1.24.13) that the build stage depends on, and the Makefile targets call
the script/ entrypoints. make fmt also formats Markdown with prettier.

Fixes for the new lint findings: the auth cookie is always Secure, an
IRC connection's relay goroutine stops when the connection closes, and
repeated strings are constants.

Model: opus-5-5

Makefile

@@ -1,15 +1,25 @@
-.PHONY: all build lint fmt fmt-check test check clean run debug docker hooks ensure-web-dist
+.PHONY: all bootstrap setup build lint fmt fmt-check test check clean run debug docker hooks ensure-web-dist
 
 BINARY := neoircd
 VERSION := $(shell git describe --tags --always --dirty 2>/dev/null || echo "dev")
 LDFLAGS := -X main.Version=$(VERSION)
 
+# The standard targets are thin shims; the implementations live in
+# script/ per the scripts-to-rule-them-all pattern (see the Entrypoints
+# section of README.md).
+
 all: check build
 
+bootstrap:
+	@script/bootstrap
+
+setup:
+	@script/setup
+
 # ensure-web-dist creates placeholder files so //go:embed dist/* in
 # web/embed.go resolves without a full Node.js build.  The real SPA is
 # built by the web-builder Docker stage; these placeholders let
-# "make test" and "make build" work outside Docker.
+# "make build" work outside Docker.
 ensure-web-dist:
 	@if [ ! -d web/dist ]; then \
 		mkdir -p web/dist && \
@@ -20,25 +30,20 @@ ensure-web-dist:
 build: ensure-web-dist
 	go build -ldflags "$(LDFLAGS)" -o bin/$(BINARY) ./cmd/neoircd
 
-lint: ensure-web-dist
-	golangci-lint run --config .golangci.yml ./...
+test:
+	@script/test
+
+lint:
+	@script/lint
 
 fmt:
-	gofmt -s -w .
-	goimports -w .
+	@script/fmt
 
 fmt-check:
-	@test -z "$$(gofmt -l .)" || (echo "Files not formatted:" && gofmt -l . && exit 1)
+	@script/fmt-check
 
-test: ensure-web-dist
-	go test -timeout 120s -race -cover ./...
-
-# check runs all validation without making changes
-# Used by CI and Docker build — fails if anything is wrong
-check: test lint fmt-check
-	@echo "==> Building..."
-	go build -ldflags "$(LDFLAGS)" -o /dev/null ./cmd/neoircd
-	@echo "==> All checks passed!"
+check:
+	@script/check
 
 run: build
 	./bin/$(BINARY)
@@ -50,10 +55,7 @@ clean:
 	rm -rf bin/ neoircd
 
 docker:
-	docker build -t neoirc .
+	@script/docker
 
 hooks:
-	@printf '#!/bin/sh\nset -e\n' > .git/hooks/pre-commit
-	@printf 'go mod tidy\ngo fmt ./...\ngit diff --exit-code -- go.mod go.sum || { echo "go mod tidy changed files; please stage and retry"; exit 1; }\n' >> .git/hooks/pre-commit
-	@printf 'make check\n' >> .git/hooks/pre-commit
-	@chmod +x .git/hooks/pre-commit
+	@script/install-precommit