feat: localchat, a Go + Templ + HTMX chat app for local Gemma models

Streams replies over SSE from any OpenAI-compatible server (oMLX,
llama.cpp, Ollama, ...). Single binary that can install itself as an
OS service; docker compose bundles llama.cpp + Gemma 4 E2B.

Makefile

@@ -0,0 +1,34 @@
+VERSION ?= $(shell git describe --tags --always --dirty 2>/dev/null || echo dev)
+LDFLAGS := -s -w -X main.version=$(VERSION)
+PLATFORMS := linux/amd64 linux/arm64 darwin/arm64 darwin/amd64 windows/amd64 windows/arm64
+
+.PHONY: generate build run test e2e dist up down
+
+generate:            ## regenerate Templ components
+	go tool templ generate
+
+build: generate      ## build ./bin/localchat for this machine
+	go build -trimpath -ldflags "$(LDFLAGS)" -o bin/localchat ./cmd/localchat
+
+run: build           ## run in the foreground (reads ./.env)
+	./bin/localchat --debug
+
+test:                ## unit + handler tests (no model needed)
+	go test -race ./...
+
+e2e:                 ## browser test against a running instance + real model
+	uv run scripts/e2e.py
+
+dist: generate       ## cross-compile for every platform into ./dist
+	@for p in $(PLATFORMS); do \
+		os=$${p%/*}; arch=$${p#*/}; ext=$$( [ $$os = windows ] && echo .exe ); \
+		echo "  $$os/$$arch"; \
+		CGO_ENABLED=0 GOOS=$$os GOARCH=$$arch go build -trimpath -ldflags "$(LDFLAGS)" \
+			-o dist/localchat-$$os-$$arch$$ext ./cmd/localchat || exit 1; \
+	done
+
+up:                  ## start app + llama.cpp + Gemma in containers
+	docker compose up -d --build
+
+down:
+	docker compose down