[zhangzhenghao]

Changes

• Move CLI source files and integration tests from cmd/gorse-cli to the repository root.
• Move internal/version into the root main package and update version output.
• Update CI, GoReleaser entry point/linker flags, and documented build commands.

Verification

• CI run 39967839319 passed on ec89559: go test ./..., go vet ./..., root build, and install.sh syntax check.
• Locally built with CGO_ENABLED=0 and injected main.Version/main.GitCommit/main.BuildTime; --version confirmed all injected values.
• Verified unchanged source/test files are byte-for-byte moves; git diff --check passed.
• Local vet attempt was blocked by a full /mnt/openclaw filesystem; remote vet passed.