fix: document wc, expose help, and correct newline counting

[hengyunabc]

The wc pipe handler lacks usable command help and dedicated documentation. Its current counter also drops blank lines and can count the same line twice when output arrives in separate writes.

This change registers wc with the command framework so help wc, wc -h, and wc --help work, and shares the -l / --lines option definition with the pipe handler. It adds Chinese and English documentation, command-list links, sidebar entries, and help-list examples.

The counter now counts \n characters using an atomic long. Blank lines count, CRLF counts once, and an unterminated final line does not add a count. Results no longer depend on write boundaries. The help/documentation work and counting fix are kept in separate commits.

Validation:

• JDK 17: ./mvnw -B -ntp -pl core -am test passed, including 322 core tests (0 failures/errors; 7 existing skips) and dependency-module tests.
• Added coverage for command registration, general and detailed help, the shell help execution path, both line-count options, independent counters, blank lines, unterminated text, CRLF, fragmented output, and concurrent writes. All six new counting regression cases failed before the fix and passed afterward.
• npm --prefix site run docs:build passed (158 pages); verified rendered examples, counting rules, and Chinese/English command-list and sidebar links.
• git diff origin/master...HEAD --check passed.

Full distribution packaging is not verified: a local package attempt passed the tests but stopped because the Web UI build output at web-ui/arthasWebConsole/dist/ui was absent.

Related to #2322.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-12T12:29:02.323484Z	9881d43	PR opened

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