test: make CLI goldens timezone- and CRLF-independent, gate scale test to Unix (#509)

Follow-up to #508. With release builds and `--no-fail-fast`, the Windows
run showed exactly two remaining failures out of the full suite.

## cli_simplify goldens
The fixture commits with `GIT_AUTHOR_DATE=@1700000000` and no offset, so
git stamps the machine's local timezone into each commit and the SHAs
change with it. The goldens were generated at +0530, so the test only
passed on machines in that zone. It failed on the UTC Windows runner and
on a US-timezone Mac. The fixture now pins `+0530`, which matches the
existing goldens without regenerating them. Golden files are also read
with CRLF normalized, since a Windows checkout converts them.

Verified locally: 15/15 pass with TZ unset (America/Los_Angeles), TZ=UTC
and TZ=America/New_York.

## arch_diff_scale
The test exists to hold arch-diff under 1 GB on a 50k-file repo, and it
reads peak memory with `ps`, which Windows does not have (the run
reported `peak 0 MB`). Generating the 50k files also took 465s on the
Windows filesystem. Gated to `#[cfg(unix)]`, matching how the
memory-budget test in arch_diff_review was gated.

Author: rs545837

CHANGELOG.md

@@ -7,6 +7,7 @@ All notable changes to sem are documented in this file.
 ### Changed
 
 - **Windows CI runs the test suite against release builds and reports every failure.** The wall-time and scale tests are calibrated for optimized binaries, so the debug build on the Windows runner overran them and failed main on four pushes in a row, each time on a different test because `cargo test` stopped at the first failing binary. Tests now build in release on the same target as the build step, and `--no-fail-fast` shows all failures at once.
+- **The CLI golden tests pass in every timezone and on Windows.** The fixture committed with a bare Unix timestamp, so git stamped the machine's local timezone into each commit and the SHAs in the goldens only matched machines set to +0530; the fixture now pins that offset. The comparison also ignores the CRLF line endings a Windows checkout gives the golden files. The 50k-file memory-bound test runs only on Unix, since it reads peak memory with `ps`, which Windows does not have.
 
 - TS/JS import edits preserve exact UTF-8 byte ranges and surrounding same-line code. Duplicate detection uses parsed declarations, and unavailable/invalid parsing refuses edits without changing the file rather than falling back to text matching.
 

crates/sem-cli/tests/arch_diff_scale.rs

@@ -120,6 +120,9 @@ fn run_bounded(dir: &Path, max_mb: u64, max_secs: u64) -> Result<(u64, f64, Stri
     }
 }
 
+// Peak memory is read with ps(1), which Windows lacks, so the bound this test
+// exists to hold cannot be measured there.
+#[cfg(unix)]
 #[test]
 fn a_tiny_change_in_a_50k_file_repo_stays_under_a_gigabyte() {
     let tmp = tempfile::tempdir().unwrap();

crates/sem-cli/tests/cli_simplify.rs

@@ -53,14 +53,14 @@ fn fixture() -> TempDir {
     )
     .unwrap();
     git(r, &["add", "-A"], None);
-    git(r, &["commit", "-qm", "init"], Some("@1700000000"));
+    git(r, &["commit", "-qm", "init"], Some("@1700000000 +0530"));
     fs::write(
         r.join("src/config.py"),
         "def parse_config(text):\n    pairs = [line.split(\"=\", 1) for line in text.splitlines() if line]\n    return dict(pairs)\n\n\ndef load(path):\n    with open(path) as f:\n        return parse_config(f.read())\n\n\ndef main():\n    print(load(\"app.cfg\"))\n",
     )
     .unwrap();
     git(r, &["add", "-A"], None);
-    git(r, &["commit", "-qm", "change"], Some("@1700000100"));
+    git(r, &["commit", "-qm", "change"], Some("@1700000100 +0530"));
     dir
 }
 
@@ -389,8 +389,10 @@ fn goldens_old_invocations_and_their_new_spellings() {
             fs::write(&path, normalize(&out.stdout, repo.path())).unwrap();
             continue;
         }
+        // A Windows checkout may convert the goldens to CRLF; sem prints LF.
         let golden = fs::read_to_string(&path)
-            .unwrap_or_else(|_| panic!("missing golden {}", path.display()));
+            .unwrap_or_else(|_| panic!("missing golden {}", path.display()))
+            .replace("\r\n", "\n");
         for argv in std::iter::once(*old).chain(news.iter().copied()) {
             let out = sem(repo.path(), cache.path(), argv);
             let got = normalize(&out.stdout, repo.path());
@@ -795,7 +797,7 @@ fn impact_diff_tests_in_a_js_workspace_is_the_module_graph_selection() {
     )
     .unwrap();
     git(r, &["add", "-A"], None);
-    git(r, &["commit", "-qm", "init"], Some("@1700000000"));
+    git(r, &["commit", "-qm", "init"], Some("@1700000000 +0530"));
     fs::write(
         r.join("src/math.ts"),
         "export function add(a: number, b: number) { return b + a; }\n",