Add a make package target for versioned Linux CLI release tarballs

Bundles deck-engine, interpreter-cli, run-engine.sh/run-interpreter.sh,
img/, i18n/, LICENSE, README.md, and docs/reading.md into
dist/deck-in-a-dash-<version>-linux-<arch>.tar.gz. Version defaults to
the current git tag (vX.Y.Z), falling back to a 0.0.0-dev+<sha>
placeholder when untagged

CLAUDE.md

@@ -19,6 +19,7 @@ make          # builds dist/{deck-engine,interpreter-cli}, dist/img/, dist/i18n/
               # dist/run-engine.sh, dist/run-interpreter.sh, dist/user.properties
 make test     # builds and runs engine/tests/smoke_test.c and interpreter/tests/*_test.c
 make clean    # removes build/ and the generated binaries/img/i18n (never touches dist/user.properties)
+make package  # builds a versioned Linux CLI tarball at dist/ - see "Packaging" below
 ```
 
 A single `Makefile` at the repo root builds both `engine/` and
@@ -63,6 +64,36 @@ Run a single smoke test by editing `engine/tests/smoke_test.c`'s `main()`
 temporarily, or just read its assertions — there's no test filter flag,
 the whole suite runs in milliseconds.
 
+## Packaging
+
+`make package` (a `Makefile` target, not a separate script) builds a
+fresh `all` and bundles it into a versioned, self-contained Linux CLI
+tarball at `dist/deck-in-a-dash-<version>-linux-<arch>.tar.gz` -
+`deck-engine`, `interpreter-cli`, `run-engine.sh`/`run-interpreter.sh`,
+`img/`, `i18n/`, `LICENSE`, `README.md`, `docs/reading.md` (renamed
+`READING.md`), and a placeholder `user.properties` (from
+`engine/scripts/user.properties.template`, **never**
+`dist/user.properties` itself - see below). Extracting the tarball
+anywhere and running the scripts/binaries from inside it works exactly
+like running them from `dist/` in place, since `run-engine.sh`/
+`run-interpreter.sh` already resolve every path relative to their own
+location (`SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"`), not the
+caller's working directory.
+
+**Version**: defaults to the current commit's git tag, matching
+`vX.Y.Z` (the `v` is stripped); if `HEAD` isn't exactly on such a tag,
+it falls back to a `0.0.0-dev+<short-sha>` placeholder with a warning on
+stderr. Override either with `make package VERSION=1.2.3`. Push a
+`vX.Y.Z` tag to drive a real release version.
+
+**Never packages `dist/user.properties`**: the staging step copies
+files into the package by explicit name only - never a wildcard or
+recursive copy of `dist/` itself - specifically so a filled-in
+`dist/user.properties` (real birth data, gitignored, private) can never
+end up in a distributable package. The package always gets the
+placeholder template instead, identical to what a first-time `make`
+seeds `dist/user.properties` with.
+
 ## Architecture
 
 ```
@@ -91,8 +122,10 @@ deck_in_a_dash/
     tests/smoke_test.c
     scripts/run-engine.sh, scripts/run-interpreter.sh, scripts/user.properties.template
   interpreter/                  Separate module + binary; see "Interpretation" below.
-  dist/                         Build output (gitignored-style; see Build & run).
-  Makefile                      Single root Makefile, builds both engine/ and interpreter/.
+  dist/                         Build output (gitignored-style; see Build & run) and,
+                                 after `make package`, versioned release tarballs.
+  Makefile                      Single root Makefile, builds both engine/ and
+                                 interpreter/, and packages a release (see Packaging).
 ```
 
 ### Data flow / the real API

Makefile

@@ -76,7 +76,11 @@ JSON_TEST_BIN         := $(BUILD_DIR)/json_test
 NARRATIVE_TEST_BIN    := $(BUILD_DIR)/narrative_test
 GUIDANCE_TEST_BIN     := $(BUILD_DIR)/guidance_test
 
-.PHONY: all test clean images i18n scripts
+# Linux CLI release tarball - see the `package` target below.
+ARCH        := $(shell uname -m)
+PACKAGE_DIR := $(BUILD_DIR)/package
+
+.PHONY: all test clean images i18n scripts package
 
 all: $(ENGINE_BINARY) $(INTERP_BINARY) images i18n scripts
 
@@ -152,6 +156,47 @@ $(OBJ_DIR)/%.o: %.c
 	@mkdir -p $(dir $@)
 	$(CC) $(CFLAGS) -c -o $@ $<
 
+# Builds a versioned Linux CLI release tarball at
+# dist/deck-in-a-dash-<version>-linux-<arch>.tar.gz. Version defaults to
+# the current git tag (vX.Y.Z, tag prefix stripped) - push a tag to drive
+# a release. Override with `make package VERSION=1.2.3`, or just run it
+# untagged for a local dev build (gets a 0.0.0-dev+<sha> placeholder
+# version, with a warning).
+#
+# Copies files into the staging dir by explicit name only - never a
+# wildcard/recursive copy of dist/ itself - so a real, filled-in
+# dist/user.properties (birth data, gitignored, private) can never
+# accidentally end up in a package. The package gets the placeholder
+# template instead, same as a first-time `make` produces.
+package: all
+	@V="$(VERSION)"; \
+	if [ -z "$$V" ]; then \
+		if TAG=$$(git describe --tags --exact-match --match 'v[0-9]*.[0-9]*.[0-9]*' 2>/dev/null); then \
+			V=$${TAG#v}; \
+		else \
+			V="0.0.0-dev+$$(git rev-parse --short HEAD)"; \
+			echo "WARNING: HEAD is not on a vX.Y.Z tag - building placeholder version $$V (push a tag to drive a real release version)" >&2; \
+		fi; \
+	fi; \
+	case "$$V" in \
+		[0-9]*.[0-9]*.[0-9]*) ;; \
+		*) echo "PREFLIGHT FAIL: VERSION '$$V' is not a semantic version (expected X.Y.Z, optionally with a -pre+meta suffix)" >&2; exit 1;; \
+	esac; \
+	PKG_NAME="deck-in-a-dash-$$V-linux-$(ARCH)"; \
+	PKG_STAGE="$(PACKAGE_DIR)/$$PKG_NAME"; \
+	echo "Packaging $$PKG_NAME"; \
+	rm -rf "$$PKG_STAGE"; \
+	mkdir -p "$$PKG_STAGE"; \
+	cp $(ENGINE_BINARY) $(INTERP_BINARY) "$$PKG_STAGE/"; \
+	cp $(DIST_DIR)/run-engine.sh $(DIST_DIR)/run-interpreter.sh "$$PKG_STAGE/"; \
+	cp -r $(DIST_IMG_DIR) $(DIST_I18N_DIR) "$$PKG_STAGE/"; \
+	cp $(ENGINE_SCRIPTS_DIR)/user.properties.template "$$PKG_STAGE/user.properties"; \
+	cp LICENSE README.md "$$PKG_STAGE/"; \
+	cp docs/reading.md "$$PKG_STAGE/READING.md"; \
+	tar -czf "$(DIST_DIR)/$$PKG_NAME.tar.gz" -C "$(PACKAGE_DIR)" "$$PKG_NAME"; \
+	rm -rf "$(PACKAGE_DIR)"; \
+	echo "Wrote $(DIST_DIR)/$$PKG_NAME.tar.gz"
+
 clean:
 	rm -rf $(BUILD_DIR) $(ENGINE_BINARY) $(INTERP_BINARY) $(DIST_IMG_DIR) $(DIST_I18N_DIR) \
 		$(DIST_DIR)/run-engine.sh $(DIST_DIR)/run-interpreter.sh

README.md

@@ -53,7 +53,8 @@ interpreter/                     Separate module + binary (dist/interpreter-cli)
                                   --format text|html|json and --lang en|de for
                                   its own output too (see CLAUDE.md).
 docs/                            Architecture/dataflow diagrams, input/output format reference.
-Makefile                         Single root Makefile, builds both engine/ and interpreter/.
+Makefile                         Single root Makefile, builds both engine/ and
+                                  interpreter/, and packages a release (`make package`).
 ```
 
 See [`CLAUDE.md`](CLAUDE.md) for the detailed architecture and the sharp
@@ -69,6 +70,10 @@ struct format reference
 make          # -> dist/deck-engine, dist/interpreter-cli, dist/img/, dist/i18n/,
               #    dist/run-engine.sh, dist/run-interpreter.sh, dist/user.properties
 make test     # builds and runs engine/tests/smoke_test.c and interpreter/tests/*_test.c
+make package  # -> dist/deck-in-a-dash-<version>-linux-<arch>.tar.gz, a
+              #    self-contained release bundle (binaries, scripts, img/, i18n/,
+              #    LICENSE, docs) - version from the current git tag, or
+              #    VERSION=1.2.3 make package to override
 ```
 
 Requires only a C99 compiler and `make` — no other dependencies.