feat(twitch): Add Twitch token refresh

[Nebhay]

Summary

This PR integrates Twitch token refreshing into Spacebot using twitch-irc’s RefreshingLoginCredentials, adds persistent storage of Twitch access/refresh tokens,

The end result:

• Twitch bot connects to chat using a user access token that can expire.
• Access tokens are automatically refreshed while Spacebot is running.
• Updated access/refresh tokens are persisted to disk so Spacebot can restart without re-auth.
• Twitch config can be managed entirely via the Spacebot UI (username, client id, client secret, access token, refresh token).

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Details

Twitch token storage and refreshing

• Implemented TwitchTokenStorage in interface/src/components/ChannelEditModal.tsx as a TokenStorage for RefreshingLoginCredentials:

  • Stores:
    • access_token: String
    • refresh_token: String
    • token_path: Option<PathBuf>
  • load_token():
    • If token_path is set and the file exists, read twitch_token.json and load:
      • access_token
      • refresh_token
      • created_at: Option<DateTime<Utc>>
      • expires_at: Option<DateTime<Utc>>
    • If no file or parse fails, fall back to in-memory values (from config/UI).
    • Always writes back a TwitchTokenFile to twitch_token.json containing:
      • access_token
      • refresh_token
      • created_at (either the stored time or now)
      • expires_at (if known)
    • Returns a UserAccessToken with those fields.
  • update_token():
    • Called by twitch-irc when refresh succeeds.
    • Updates in-memory access_token/refresh_token and timestamps from UserAccessToken.
    • Overwrites twitch_token.json with the new values.

• Switched Twitch IRC client creation to RefreshingLoginCredentials<TwitchTokenStorage>:

  • Extracts the initial access token from config (strips oauth: prefix if present).
  • Seeds TwitchTokenStorage with:
    • access_token from config
    • refresh_token from config/UI or twitch_token.json
    • token_path pointing at ~/.spacebot/twitch_token.json for the active instance dir.
  • Uses RefreshingLoginCredentials::init(client_id, client_secret, storage) to let twitch-irc:
    • Use the refresh token + client_id/client_secret to call Twitch’s /oauth2/token.
    • Refresh tokens automatically when they are invalid/expired.
    • Persist new tokens via our update_token() implementation.

• Extended TwitchTokenFile to include timing metadata:

  • created_at: Option<DateTime<Utc>>
  • expires_at: Option<DateTime<Utc>>
  • Allows us to keep a stable creation timestamp across restarts and optionally track expiry if Twitch returns it.

Adapter construction and token file path

• Standardized the token file name and path:

  • All Twitch adapter entry points now use:
    • token_path = instance_dir.join("twitch_token.json")
  • This is wired in:
    • Daemon startup (src/main.rs)
    • API messaging toggle path (src/api/messaging.rs)
    • Bindings hot-start (src/api/bindings.rs)
    • Config file watcher hot-start (src/config.rs)

• Updated TwitchAdapter::new signature and all call sites to pass:

  1. username
  2. oauth_token
  3. client_id
  4. client_secret
  5. refresh_token
  6. token_path (Some(instance_dir.join("twitch_token.json")))
  7. channels
  8. trigger_prefix
  9. permissions (Arc<ArcSwap<TwitchPermissions>>)

Config and API wiring

• Extended Twitch config model to support the new credentials:
  • TOML / config:
    • [messaging.twitch] now supports:
      • username
      • oauth_token
      • client_id
      • client_secret
      • refresh_token
      • channels = ["..."]
      • trigger_prefix
  • API types and handlers:
    • platform_credentials for Twitch now includes:
      • twitch_username
      • twitch_oauth_token
      • twitch_client_id
      • twitch_client_secret
      • twitch_refresh_token
    • When Twitch is configured via the UI, the backend:
      • Writes these fields into the Spacebot config.
      • Ensures the Twitch adapter is enabled/started with the correct token path.

UI updates (Twitch credentials)

• Updated ChannelEditModal Twitch section in interface/src/components/ChannelEditModal.tsx:
  • New fields:
    • Bot Username
    • Client ID
    • Client Secret (password input)
    • OAuth Access Token (password input)
    • OAuth Refresh Token (password input)
  • handleSaveCredentials() populates platform_credentials with:
    • twitch_username
    • twitch_oauth_token
    • twitch_client_id
    • twitch_client_secret
    • twitch_refresh_token
  • Helper text explains:
    • Tokens should come from the user’s Twitch application.
    • chat:read and chat:write scopes must be enabled.
    • Tokens are stored in the Spacebot instance and refreshed automatically while running.