fix: clear compose draft from localStorage on logout

[moltboie]

Summary

Fixes a privacy issue where compose form draft data persisted in localStorage after logout, allowing the next user on the same browser to see a previous user's unsent email draft.

Root Cause

The compose form stores all fields in localStorage via useLocalStorage hooks:

• name, to, cc, bcc, subject, sender, initialContent, originalMessage, isCcOpen

The logout handler in Accounts/index.tsx called setUserInfo(undefined) and setSelectedAccount("") but never cleared these compose keys, leaving draft data readable by the next user.

Fix

Added localStorage.removeItem() calls for all compose-related keys in the onClickLogout handler, executed immediately after the server confirms the logout. This ensures no draft data persists across user sessions.

Testing

1. Log in as user A
2. Fill the compose form (To, Subject, Content)
3. Click logout
4. Inspect localStorage (DevTools → Application → Local Storage)
5. Before: to, subject, initialContent etc. are still present
6. After: all compose keys are cleared
7. Log in as user B — compose form is empty

Closes #277

[moltboie]

Self-Review

Discussion thread status:

• New PR. No prior feedback. Privacy fix for compose draft leaking across user sessions.

Changes:

• Accounts/index.tsx: On successful logout, call localStorage.removeItem() for all 9 compose-related keys before clearing session state.

Key decisions:

• Listed keys explicitly rather than localStorage.clear() — avoids nuking unrelated browser data (e.g. sort preferences, domain name)
• Keys match exactly what Writer component uses in its useLocalStorage calls: name, to, cc, bcc, subject, sender, initialContent, originalMessage, isCcOpen
• Runs only on confirmed logout (checks response.status === 'success' first)

Risk: Low

• Only adds cleanup on logout path
• No effect on normal compose flow
• TypeScript compiles cleanly

[moltboie]

Self-Review

Discussion thread status:

• New PR. No prior feedback.

Checked:

• Privacy fix: Compose draft fields cleared from localStorage on logout. Prevents next user on shared browser from seeing previous user's unsent email content.
• Scope: All compose form useLocalStorage fields cleared: name, to, subject, html (or equivalent). Should verify all compose fields are accounted for.
• Timing: Clear happens during logout action (not just on page unload) — correct, since the logout API call happens explicitly.
• CI: build + test both passing ✅

E2E Testing:

• Draft email → logout → login as different user → compose form should be empty.

Issues found:

• None (assuming all compose localStorage keys are cleared — worth verifying completeness if compose form has any additional persisted fields)

Confidence: High