feat(settings): add passkey-context copy to FlowSetup2faPrompt

[vbudhram]

Because

• When a relying party requires two-step authentication and the user signed in with a passkey, the current copy is misleading. It says the service "requires you to set up two-step authentication to keep your account safe", but the passkey ceremony already authenticated the user. The setup protects the other sign-in methods, not the passkey path.
• UX has finalized the replacement copy.

This pull request

• Adds a success banner ("Successfully signed in with passkey") and swaps the body copy on FlowSetup2faPrompt when the session came from a passkey. Page label, heading, authenticator-apps line, and Continue button are unchanged.
• Adds two FTL ids and leaves the existing ids alone. The new body string reuses the shared -product-mozilla-account term.
• Wires the signal end to end. isPasskeySession already reached handleNavigation from the passkey sign-in flow but was dropped by createSigninLocationState; it now survives into SigninLocationState and flows through the InlineTotpSetup container to the prompt.
• An error banner replaces the success banner rather than stacking with it.
• Unit tests cover the propagation and both copy paths; the two AAL2 passkey functional tests assert the banner.

Caveat: the flag lives in router state, so a hard reload of /inline_totp_setup falls back to the generic copy. Reading sessionStatus().details.sessionVerificationMethod would survive reloads, but it is also true for a cached passkey session, where "Successfully signed in with passkey" would be inaccurate.

Issue that this pull request solves

Closes: https://mozilla-hub.atlassian.net/browse/FXA-13822

Checklist

Put an x in the boxes that apply

• My commit is GPG signed.
• If applicable, I have modified or added tests which pass locally.
• I have added necessary documentation (if appropriate).
• I have verified that my changes render correctly in RTL (if appropriate).
• I have manually reviewed all AI generated code.

How to review (Optional)

• Propagation path: Signin/utils.ts (createSigninLocationState) → InlineTotpSetup/container.tsx → FlowSetup2faPrompt/index.tsx.
• The l10n strings are the part worth a careful read, because new ids go to Pontoon.

Screenshots (Optional)

None. Visual fidelity was not checked. Open the Pages/InlineTotpSetup → SignedInWithPasskey story and compare against Figma node 3958-21735.

Other information (Optional)

Verification: nx lint fxa-settings and yarn compile clean; 74 tests pass across FlowSetup2faPrompt, InlineTotpSetup, and Signin/utils. Playwright not run locally.

[Copilot]

Pull request overview

This PR updates FlowSetup2faPrompt (in fxa-settings) to present clearer copy when the user has just signed in with a passkey and is being prompted to set up two-step authentication, including new localized strings, tests, and a Storybook story.

Changes:

• Added an optional signedInWithPasskey prop to conditionally show a success banner and alternate body copy.
• Added new Fluent strings (en.ftl) for the passkey success banner and passkey-specific description copy.
• Updated unit tests and Storybook stories to cover the passkey path.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
packages/fxa-settings/src/components/Settings/FlowSetup2faPrompt/index.tsx	Adds signedInWithPasskey branching for banner + description copy using Fluent resolver.
packages/fxa-settings/src/components/Settings/FlowSetup2faPrompt/index.test.tsx	Adds tests covering the new passkey banner and copy branch.
packages/fxa-settings/src/components/Settings/FlowSetup2faPrompt/index.stories.tsx	Adds a Storybook story for the passkey branch.
packages/fxa-settings/src/components/Settings/FlowSetup2faPrompt/en.ftl	Adds two new Fluent message IDs for the passkey branch.

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.