Each download of node's `index.tab` now merges every version's LTS codename, or `-`, into `$NVM_DIR/.lts-status`,
keeping versions that download doesn't list,
so the status of an installed version is known, and refreshed on every remote connection.
Only an index that includes LTS versions can start the record, so a nightly or release candidate mirror can't,
and `nvm_ensure_lts_status` downloads it once for versions installed before it was recorded.
`update_test_mocks.sh` writes the record of its `index.tab` mock to `nodejs.org-dist-lts-status.txt`.
Add `try` and `try_err` helper functions to `test/common.sh` that capture stdout/stderr and exit code from a single invocation, eliminating duplicate command executions in tests.
Convert all existing tests that used the `OUTPUT`/`EXIT_CODE` double-invocation pattern to use the new helpers.
Also fixes a pre-existing bug in the `nvm_die_on_prefix` test where ASCII apostrophes were used instead of U+2019 to match nvm.sh output.
nvm.sh uses `NVM_SCRIPT_SOURCE="$_"` to detect its source location.
Adding `: nvm.sh` before each source line ensures `$_` is set correctly, preventing breakage when the previous command (e.g., `set -ex`) overwrites it.
Jordan Harband
Dena Burd
Peter Dave Hello
Qiangjun Ran