Fix grammar and typos in syscall documentation

[minhsun-c]

Refine the system call documentation to improve readability and correct grammatical errors.

Changes include:

• Fix subject-verb agreement and pluralization in audio and input sections.
• Correct sentence fragments and punctuation in control_audio.
• Standardize terminology for "set up" (verb) vs "setup" (noun).
• Update technical phrasing for clearer assembly interactions.

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Summary by cubic

Polished syscall documentation to fix grammar and typos and make instructions clearer. Improves readability and reduces confusion around assembly calls, input queues, and audio control.

• Bug Fixes
  • Standardized terms: “assembly” (not “assembler”), “cannot”, “set up” (verb) vs “setup” (noun), and “SFX”.
  • Fixed grammar, punctuation, and subject–verb agreement in input and audio sections; corrected typos (e.g., enabled).
  • Clarified privilege modes and return instructions; corrected bit numbering (31st).
  • Tightened wording for parameter mapping and syscall number references.
  • Corrected SHUTDOWN_AUDIO to reference INIT_AUDIO, matching the enum definition.

^{Written for commit f4f11c6. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 1 file

[jserv]

Thank @minhsun-c for contributing!