refactor(scripts): functional pipelines in Nushell scripts - #1524

Summary

Applies the expression-oriented style from the Nushell book (Thinking in Nu, Nu map from functional languages) to the repo's .nu scripts. An earlier pass (#1485) removed the mut/for accumulators; what was left was side-effecting statement sequences where a pipeline expression says the same thing, plus a duplicated otool parse.

Two commits, separately revertable.

refactor(scripts): replace side-effecting loops with Nushell pipelines

• pricing-lock.nu — report called save --append once per line inside each, then discarded the resulting list of nothings with ignore. to text already renders a list as newline-terminated lines, so this is one append with no per-iteration side effect.
• generate-e2e-fixture.nu — dropped a let lines binding that existed only to be immediately joined, and removed a redundant $"(...)" interpolation wrapping an already-string claude_line result.
• upsert-pr-comment.nu — the request body was staged in a mktemp file, passed as gh api --input <path>, then removed. gh api --input - reads stdin and $in forwards pipeline input to an external inside a custom command, so the temp file, its save, and its rm are gone.

refactor(scripts): share otool parsing between native package scripts

ensure-native-binary.nu and stage-native-package.nu each defined binary_name and each parsed otool -L output. The two parses had already drifted — the staging copy kept blank rows the checking copy filtered. Both now come from a new apps/ccusage/scripts/native-binary.nu module, following the pricing-lock.nu precedent for a shared non-executable module.

linked-dylibs returns {ok, stderr, dylibs} instead of erroring, because the callers want different failure handling: staging aborts with the captured stderr, the portability check treats an otool failure as not portable.

Drive-by bug fix

Selecting dylib rows by their tab indent instead of skip 1 fixes a latent bug. otool -L repeats an unindented <binary> (architecture <arch>): header once per architecture:

/bin/ls (architecture x86_64):
	/usr/lib/libutil.dylib (compatibility version 1.0.0, ...)
/bin/ls (architecture arm64e):     <-- skip 1 did not drop this
	/usr/lib/libutil.dylib (compatibility version 1.0.0, ...)

skip 1 dropped only the first header and fed the rest through as linked libraries, so any fat binary was reported as depending on itself — and since a binary path starts with neither /usr/lib/ nor /System/Library/, the portability check failed it. Cargo emits single-architecture binaries, so the shipped path never hit this.

Verification

• nu-check passes on all 9 .nu files; just fmt (treefmt/nufmt) reports no changes.
• generate-e2e-fixture.nu output is byte-identical to before (291880 bytes, same sha1).
• pricing-lock.nu report appends the same changed=/paths= lines across repeated calls.
• upsert-pr-comment.nu driven end to end against a stub gh covering create, update, HTTP 404 recreate, and HTTP 403 skip — body arrives as correct JSON on stdin in every write path, and the marker match still picks the github-actions[bot] comment over another author's.
• linked-dylibs compared against both previous implementations on real Mach-O binaries: identical for single-architecture input; /bin/ls now reports its 6 real dylibs and passes the portability check instead of failing it.
• Full darwin staging cycle run over a nix-store binary that links nix-store libiconv, confirming the install_name_tool rewrite to /usr/lib/libiconv.2.dylib, the chmod 755, and the prepack verification all still pass. Test artefacts removed.

No user-facing behaviour changes, so no docs impact.

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Summary by cubic

Refactors Nushell scripts to use functional pipelines and centralizes Mach-O dylib parsing to remove side effects and duplicate code. Fixes dylib parsing for fat binaries on macOS. No user-facing changes.

• Refactors

  • Replaced loop-based writes with pipelines in .github/scripts and now stream JSON bodies to gh api via stdin (no temp files).
  • Extracted binary-name and linked-dylibs into apps/ccusage/scripts/native-binary.nu, used by ensure-native-binary.nu and stage-native-package.nu.

• Bug Fixes

  • Parse otool -L output by selecting tab-indented rows, correctly handling fat binaries with repeated headers.
  • Darwin portability check now evaluates actual dylibs; behavior unchanged for single-arch binaries.

^{Written for commit 411fded. Summary will update on new commits.}

Summary by CodeRabbit

• Bug Fixes

  • Improved native binary packaging checks across supported platforms.
  • Strengthened macOS library validation and error handling.
  • Improved reliability when generating test fixtures and reporting workflow outputs.
  • Streamlined automated pull request comment updates by handling request data more reliably.

• Refactor

  • Consolidated native binary naming and dependency inspection into shared tooling for more consistent packaging behavior.