refactor(zsh): normalize option spellings

[ss-o]

Description

Normalize Zi's separator-free multiword Zsh option spellings to canonical underscore-separated names:

• update 428 occurrences across source, scripts, tests, and nearby comments;
• cover 31 equivalent option pairs, including local_options, no_auto_pushd, extended_glob, warn_create_global, ksh_arrays, err_exit, no_unset, and pipe_fail;
• update static setopt, unsetopt, emulate -o, [[ -o ... ]], $options[...], and generated option arguments; and
• preserve option names originating dynamically from captured runtime state or user input.

Future authoring guidance is owned by z-shell/.github#566. This PR intentionally adds no narrow repository CI guard.

Related issues

Part of #449.
Part of z-shell/.github#565.

Type of change

• fix - bug fix (non-breaking)
• feat - new feature (non-breaking)
• feat! / fix! - breaking change
• perf - performance improvement
• refactor - code change with no functional impact
• docs - documentation only
• test - test addition or correction
• build - build system or dependency change
• ci - CI/workflow change
• style - formatting with no behavior change
• chore - maintenance / dependency bump
• revert - revert of an earlier change

Checklist

• Ordinary work targets next; only same-repository hotfixes target main
• This is not a next to main promotion
• Commit messages follow Conventional Commits format
• No Co-authored-by trailer credits a bot, AI agent, or automation
• I have read the contribution guidelines
• Existing tests pass
• Canonical organization guidance is provided by docs(zsh): require canonical option spellings .github#566

Verification

• All 31 old/new spelling pairs resolved to the same Zsh option state.
• A scan against 197 canonical names from the official Zsh Options manual found no remaining compact multiword spellings.
• Native syntax and isolated zcompile -U: all 31 Zsh files passed. The pre-existing lib/zsh/rpm2cpio.zsh:54 warning remains.
• Existing Zi integration suites: 61 scenarios passed.
• git diff --check: passed.
• Local commit hook: passed.

Migration plan

Not required. Zsh accepts both spellings; this is a readability-only normalization with semantic equivalence verified.

Agent handoff

• Status: Ready for review
• Current state: The option spelling cleanup is complete on bug-449-option-spelling and linked to its canonical organization guidance.
• Blockers: None. A rebase may be needed after fix(update): make parallel updater deterministic #453 and fix(callbacks): persist Plugin Standard callbacks by effective ID #454 merge because all three isolated branches started from the same next revision.
• Next steps: Review after fix(update): make parallel updater deterministic #453, fix(callbacks): persist Plugin Standard callbacks by effective ID #454, and docs(zsh): require canonical option spellings .github#566. Continue the other duplicate-helper and snippet-ID work in refactor(core): consolidate duplicate helpers and naming drift #449 separately.
• Related tracker/issues: refactor(core): consolidate duplicate helpers and naming drift #449, initiative: restore truthful Zi lifecycle and update contracts .github#565, docs(zsh): require canonical option spellings .github#566