Add support for multiple GitHub accounts

[Copilot]

Implements multiple account management, allowing users to sign in with multiple GitHub accounts and switch between them without logging out.

Changes

Account Management Service

• services/accountService.ts: Centralized account operations (add, remove, switch, get active)
• Storage structure: { accounts: Account[], activeAccountId: string } in localStorage
• Auto-migrates legacy single-account data (gh_token, gh_user) on first load
• Per-account cache isolation with accountId-prefixed keys

UI Components

• components/AccountSwitcher.tsx: Dropdown in header showing all accounts
  • Switch accounts on click
  • Add new accounts via "+ Add Account"
  • Remove accounts (hover → X button, protected when single account)
  • Full keyboard navigation with focus:opacity-100

Cache Scoping

• services/cacheService.ts: Added optional accountId parameter to getCached/setCache
• Cache keys: vibe_github_cache_{accountId}_{resource} prevents data leakage between accounts
• All views updated to pass accountId for cache operations

Application Flow

• App.tsx: Account state management replaces direct localStorage access
• views/TokenGate.tsx: "Add Account" mode with cancel flow
• views/Dashboard.tsx: Renders AccountSwitcher, reloads data on account change
• views/RepoDetail.tsx, views/IssueDetail.tsx: Account-scoped caching

Example

// Add account after GitHub OAuth
const account = addAccount(token, user);

// Switch active account
setActiveAccount('username');

// Cache scoped per account
setCache(CacheKeys.repos(), data, accountId);

Screenshot

Account switcher appears in header once logged in, displaying avatar/username with dropdown for account operations.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Add support for multiple accounts </issue_title>
<issue_description></issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Add support for multiple accounts  #13

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[github-actions]

🚀 Netlify Deployment

Deploy URL: https://694a48d39cd2d1b2b243fe48--my-test-site3.netlify.app

Branch: copilot/add-support-for-multiple-accounts
Commit: bd51529

[github-actions]

🚀 Netlify Deployment

Deploy URL: https://694a607a37cac130d5849ce9--my-test-site3.netlify.app

Branch: copilot/add-support-for-multiple-accounts
Commit: ac696b5

[github-actions]

🚀 Netlify Deployment

Deploy URL: https://694a6082b304bb17e1ec2c1b--my-test-site3.netlify.app

Branch: copilot/add-support-for-multiple-accounts
Commit: cc803f9

[github-actions]

🚀 Netlify Deployment

Deploy URL: https://694a6084bb74ee3333919118--my-test-site3.netlify.app

Branch: copilot/add-support-for-multiple-accounts
Commit: b346683

[github-actions]

🚀 Netlify Deployment

Deploy URL: https://694a6086648826350a20ad77--my-test-site3.netlify.app

Branch: copilot/add-support-for-multiple-accounts
Commit: da951ec