Add library build, local cluster script, and example client

Introduce a Makefile that builds libtoastyfs.a and libtoastyfs.so from the
client-side sources (client, tcp, byte_queue, message, basic) so external
programs can link against the ToastyFS client API in include/toastyfs.h.

Add cluster.sh, a convenience script that manages a local 3-node cluster
by spawning toastyfs server processes on ports 8081-8083.  Sub-commands:
up, down, status, logs, and "run <source.c>" which builds the library,
compiles the source against it, starts the cluster, runs the binary, and
tears everything down.

Add examples/example.c demonstrating synchronous PUT, GET, DELETE, and a
NOT_FOUND verification.

Fix a stack overflow in the MAIN_SERVER entry point: ServerState is ~40 MB
(MetaStore holds 4096 ObjectMeta entries) and was declared on the stack.
Heap-allocate it instead.

https://claude.ai/code/session_019DVhmc25jfzcHnmdNxzib2

Makefile

@@ -0,0 +1,81 @@
+CC      ?= gcc
+CFLAGS  ?= -Wall -Wextra -ggdb -O0
+AR      ?= ar
+
+INCLUDES = -Iquakey/include -Iinclude -I.
+
+# ---- Library (client-side only) ----
+
+LIB_SRCS = src/client.c src/tcp.c src/byte_queue.c src/message.c src/basic.c
+LIB_OBJS = $(LIB_SRCS:.c=.o)
+
+STATIC_LIB = libtoastyfs.a
+SHARED_LIB = libtoastyfs.so
+
+# ---- Server binary ----
+
+SERVER_SRCS = src/basic.c src/file_system.c src/byte_queue.c src/message.c \
+              src/tcp.c src/server.c src/main.c src/log.c src/client_table.c \
+              src/chunk_store.c src/metadata.c
+
+# ---- Client binary (random test client) ----
+
+CLIENT_SRCS = src/basic.c src/file_system.c src/byte_queue.c src/message.c \
+              src/tcp.c src/server.c src/client.c src/random_client.c src/main.c \
+              src/log.c src/client_table.c src/chunk_store.c src/metadata.c
+
+# ---- Simulation binary ----
+
+SIM_SRCS = src/basic.c src/file_system.c src/byte_queue.c src/message.c \
+           src/tcp.c src/server.c src/client.c src/random_client.c src/main.c \
+           src/log.c src/client_table.c src/invariant_checker.c src/chunk_store.c \
+           src/metadata.c quakey/src/mockfs.c quakey/src/quakey.c
+
+# ---- Default target ----
+
+all: $(STATIC_LIB) $(SHARED_LIB) toastyfs toastyfs_client toastyfs_simulation
+
+# ---- Library targets ----
+
+lib: $(STATIC_LIB) $(SHARED_LIB)
+
+$(STATIC_LIB): $(LIB_OBJS)
+	$(AR) rcs $@ $^
+
+$(SHARED_LIB): $(LIB_SRCS)
+	$(CC) $(CFLAGS) -shared -fPIC $(INCLUDES) $^ -o $@
+
+src/%.o: src/%.c
+	$(CC) $(CFLAGS) $(INCLUDES) -fPIC -c $< -o $@
+
+# ---- Binary targets ----
+
+toastyfs: $(SERVER_SRCS)
+	$(CC) $(CFLAGS) $(INCLUDES) -DMAIN_SERVER $^ -o $@
+
+toastyfs_client: $(CLIENT_SRCS)
+	$(CC) $(CFLAGS) $(INCLUDES) -DMAIN_CLIENT $^ -o $@
+
+toastyfs_simulation: $(SIM_SRCS)
+	$(CC) $(CFLAGS) $(INCLUDES) -DMAIN_SIMULATION -DFAULT_INJECTION $^ -o $@
+
+# ---- Install ----
+
+PREFIX    ?= /usr/local
+LIBDIR    ?= $(PREFIX)/lib
+INCLUDEDIR?= $(PREFIX)/include
+
+install: $(STATIC_LIB) $(SHARED_LIB)
+	install -d $(DESTDIR)$(LIBDIR)
+	install -d $(DESTDIR)$(INCLUDEDIR)
+	install -m 644 $(STATIC_LIB) $(DESTDIR)$(LIBDIR)/
+	install -m 755 $(SHARED_LIB) $(DESTDIR)$(LIBDIR)/
+	install -m 644 include/toastyfs.h $(DESTDIR)$(INCLUDEDIR)/
+
+# ---- Clean ----
+
+clean:
+	rm -f $(LIB_OBJS) $(STATIC_LIB) $(SHARED_LIB)
+	rm -f toastyfs toastyfs_client toastyfs_simulation
+
+.PHONY: all lib clean install