Support auth sign-in methods

[zbeyens]

• Auto release

🐛 Fixes ➖ N/A
🟢 95-100% confidence

Phase	🧪 Tests	🌐 Browser
Reproduced	🔴 React red test showed useSignInMutationOptions({ signInMethod: "username" }) still hit the email path before the fix.	➖ N/A
Verified	🟢 focused React/Solid auth tests, Better Auth plugin type fixtures, package typecheck/build, docs build, generated skill sync, and bun check	➖ N/A

✅ Outcome

• useSignInMutationOptions({ signInMethod: "username" }) dispatches to authClient.signIn.username.
• Default sign-in still uses signIn.email.
• Returned token seeding, Better Auth session hydration, and Convex auth query reset stay on the shared post-auth path.
• React and Solid helpers both expose plugin sign-in method support.
• The task workflow now requires the PR Fix Next auth preflight proxy #270 emoji task-style body in .agents/rules/task.mdc, generated task skill text, and docs/plans/templates/task.md.

⚠️ Caveat

• Generated auth forms still use email by default.
• No browser UI changed.

🏗️ Design

• Auth boundary: method selection stays inside createAuthMutations, so plugin methods reuse the existing post-auth behavior.
• Workflow boundary: task owns task-run PR body shape; git helpers remain transport only.
• Why not broader auth operation support: the requested gap was sign-in dispatch, and the current proof covers that path.

🧪 Verified

• bun test packages/kitcn/src/react/auth-mutations.test.tsx packages/kitcn/src/react/auth-mutations.types.test.ts
• bunx vitest run packages/kitcn/src/solid/auth-mutations.vitest.tsx packages/kitcn/src/solid/auth-mutations.types.vitest.ts
• bun --cwd packages/kitcn typecheck
• bun --cwd packages/kitcn build
• bun --cwd www build
• bun install
• bun run intent:validate
• bun run intent:stale
• bun lint:fix
• bun check
• rg -n 'PR #270|🐛 Fixes|🟢 95-100% confidence|Phase \\| 🧪 Tests \\| 🌐 Browser|✅ Outcome|⚠️ Caveat|🏗️ Design|🧪 Verified' .agents/rules/task.mdc .agents/skills/task/SKILL.md docs/plans/templates/task.md

[changeset-bot]

🦋 Changeset detected

Latest commit: 9cc6844

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
kitcn	Patch
@kitcn/resend	Patch

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Project	Deployment	Actions	Updated (UTC)
better-convex	Ready	Preview, Comment	May 27, 2026 9:42am