revert: 恢复版本号动态注入，本地构建回退为 dev

本地运行不再硬编码 0.3.3，改回 dev；build.sh 通过 git describe
注入真实 tag 并经 ldflags 覆盖 main.version。

Claude-Session: https://claude.ai/code/session_01HMRoSjvobCcuH5gbKkStFF

build.sh

@@ -8,7 +8,7 @@
 #   ARTEX_TARGET_OS=linux             One target OS in single-target mode.
 #   ARTEX_TARGET_ARCH=amd64           One target arch in single-target mode.
 #   ARTEX_TARGETS=linux/amd64,...     Comma-separated targets for multi-target mode.
-#   ARTEX_BUILD_VERSION=0.3.3        Version embedded in the binary and archive name.
+#   ARTEX_BUILD_VERSION=v0.3.3        Version embedded in the binary and archive name.
 #   ARTEX_OUTPUT=/path/to/artex       Explicit binary path in single-target mode.
 #   ARTEX_OUTPUT_DIR=dist             Directory for default binary paths.
 #   ARTEX_PACKAGE=1                   Create a zip archive for each target.
@@ -90,7 +90,13 @@ done
 command -v go >/dev/null 2>&1 || die "未检测到 Go（项目需要 Go 1.26 或更高版本）"
 
 ARTEX_GOSUMDB="${ARTEX_GOSUMDB:-sum.golang.org}"
-ARTEX_BUILD_VERSION="${ARTEX_BUILD_VERSION:-0.3.3}"
+if [ -z "${ARTEX_BUILD_VERSION:-}" ]; then
+  if command -v git >/dev/null 2>&1 && git rev-parse --is-inside-work-tree >/dev/null 2>&1; then
+    ARTEX_BUILD_VERSION="$(git describe --tags --always --dirty)"
+  else
+    ARTEX_BUILD_VERSION="dev"
+  fi
+fi
 # Release tags are commonly passed as v0.3.3; keep the binary version consistent.
 ARTEX_BUILD_VERSION="${ARTEX_BUILD_VERSION#v}"
 ARTEX_OUTPUT_DIR="${ARTEX_OUTPUT_DIR:-dist}"