Implement group invitation flow with shareable links

[big14way]

Create a complete invitation flow where admins can generate invite links and invitees can join directly.

Acceptance Criteria:

• Generate shareable URL with group ID encoded
• Landing page for invite link shows group details + join button
• Require wallet connection before joining
• Show success/error states after join attempt

Files: new file src/app/invite/[code]/page.tsx, src/components/InviteButton.tsx

[opensecretsauce]

@algora-pbc attempt

Implementing group invitation flow with shareable links (unique slug + QR code). PR incoming shortly.

[MCH-Strategies]

/attempt #48

Claiming this bounty to implement the group invitation flow using shareable links, ensuring a seamless user experience and efficient group management.

[MCH-Strategies]

/attempt #48

Ollama Connection Error: HTTPConnectionPool(host='localhost', port=11434): Max retries exceeded with url: /api/generate (Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x000001E24A393D00>: Failed to establish a new connection: [WinError 10061] No connection could be made because the target machine actively refused it'))