chore: use American spellings in comments, docs, copy and internal names

[chaance]

Summary

Switches British spellings (mostly cancelled) to American ones in comments, docs, test names, human-facing copy and internal identifiers. This is the CLI follow-up to workos/workos#76416. The monorepo syncs README.md into packages/docs/src/content/cli-readmes/cli.md, so the exit-code table fix ("Canceled") has to land here.

Renamed internal identifiers: ExitCode.CANCELED, abortIfCanceled, assertNotCanceled, the XState canceled state, the GIT_CANCELED / SCAFFOLD_CANCELED events, git:dirty:canceled, and the TUI canceled task status / outcome / content key. None of them reach JSON output, NDJSON events or telemetry. The headless adapter doesn't forward state names or git:dirty:*, and the package only ships a bin.

These cancelled values are public contracts, so they're unchanged:

• JSON error code cancelled (resolveErrorCode, configuration-recovery, preflight)
• termination.reason, installer.outcome and setup.outcome telemetry values
• the workos debug reset --json key cancelled

CLAUDE.md gains a short Spelling section that lists these contracts.

Human-readable messages also change, for example Delete canceled. and Install canceled. in the JSON error message. Error codes don't change.

Also fixes a Test failure that is currently on main. #237 added a maybeOfferSkillsUpdate() call in bin.ts, but src/test/readonly-installer.fixture.ts mocks commands/setup.js without that export, so bin-readonly-installer.integration.spec.ts fails. The fixture now stubs it.

Link to Devin session: https://app.devin.ai/sessions/b6af537d308d4266993ee86ed4f8d475
Open in Devin Desktop: https://app.devin.ai/desktop/session/b6af537d308d4266993ee86ed4f8d475?variant=devin
Requested by: @chaance

[devin-ai-integration]

I'll fix CI failures and address comments from users with write access. I'll skip comments containing "(aside)".

• Disable automatic comment, CI, and merge conflict monitoring

---

Original prompt from chance

SYSTEM:
<latest_message>
Chance Strickland (U07ABH2GKTL) [ts=1792000841.493729]: I noticed a bunch of code in our monorepo uses British English spelling. This goes against our general style guide and creates inconsistencies in the codebase and docs. Please audit the code for all instances of British spelling. Flag anything that could be considered a breaking change (for example, in public API shapes).
</latest_message>

=== BEGIN THREAD HISTORY ===
Chance Strickland (U07ABH2GKTL) [ts=1792000841.493729]: I noticed a bunch of code in our monorepo uses British English spelling. This goes against our general style guide and creates inconsistencies in the codebase and docs. Please audit the code for all instances of British spelling. Flag anything that could be considered a breaking change (for example, in public API shapes).
=== END THREAD HISTORY ===
Channel ID: D0AU8UHEVB2
Thread URL: https://work-os.slack.com/archives/D0AU8UHEVB2/p1792000841493729?thread_ts=1792000841.493729&amp;cid=D0AU8UHEVB2

The <latest_message> is the message that you should use to guide your goals + task for this session, and you should use the rest of the slack thread as context.
A [ts=...] marker on a Slack message is that message's timestamp. To act on a specific message with the slack tool (e.g. adding an emoji reaction via the reaction command), pass that value as timestamp along with the Channel ID — no extra lookup call is needed.

[greptile-apps]

Confidence Score: 5/5

[Low impact] This PR appears safe to merge; the spelling changes preserve cancellation behavior and public values.

Summary

Switches comments, docs, messages, and internal cancellation names to American spelling.

• Installer cancellation events and TUI statuses use American spelling.
• CLI cancellation messages use American spelling and keep existing error codes.
• Spelling guidance and related notes keep established cancellation contracts clear.

Author acknowledgments: chaance explicitly intends the human-readable changes, including JSON message fields. chaance reports the missing-mock integration failure also occurs on main, and that the ai-analysis.spec.ts timeout passed on rerun.

_{Reviews (1) · Last reviewed commit: "style: format readonly installer fixture" · Reviewed by Greptile}

[chaance]

Internal names aren't really that important here, the main thing is consistency in external comms in alignment with our style guide https://app.notion.com/p/workos/Writing-In-Our-Product-6975915fa9a74150916c669d562afe16?source=copy_link#81e2466abcfa4c4fb8288c40dac50eb8

However, I think updating internal names is good to keep agents consistent here as well. So I think it's worth the churn.

[devin-ai-integration]

Makes sense. The internal renames stay in so agents copy the American spelling. The only cancelled left in code is the shipped contract values listed in the new CLAUDE.md Spelling section.

[devin-ai-integration]

This PR doesn't change any part of the public cancelled contract. Every machine-readable value is unchanged from main: the JSON error code, the termination.reason / installer.outcome / setup.outcome telemetry values, the workos debug reset --json key, and exit code 2.

The cancelled → canceled changes are limited to:

• internal identifiers that never reach JSON, NDJSON or telemetry output, such as the ExitCode constant name, helpers, XState states and events, emitter event names and TUI keys
• human-readable copy, comments, docs and test names