v.help: fix typos

[ttytm]

🤖 Generated by Copilot at 9a66361

This pull request fixes several typos and improves the readability of the documentation files for various v commands and backends. It affects the files build-c.txt, build-wasm.txt, build.txt, build-js.txt, watch.txt, bug.txt, and other.txt in the vlib/v/help directory.

🤖 Generated by Copilot at 9a66361

• Fix typos in the documentation of various options and commands for the V compiler (link, link, link, link, link, link)
• Add missing words and punctuation in the documentation of the stack size option for the C backend, the browser target for the WASM backend, and the test-self command for the V compiler (link, link, link)
• Add missing blank line before the "See also" section in the documentation of the build command for the V compiler (link)