Method refreshMicrosoft

src/main/lib/credential-manager.ts:682–705

* Refresh Microsoft OAuth token

(
    source: LoadedSource,
    cred: StoredCredential
  )

   * Refresh Microsoft OAuth token
   */
  private async refreshMicrosoft(
    source: LoadedSource,
    cred: StoredCredential
  ): Promise<string | null> {
    try {
      const result = await refreshMicrosoftToken(cred.refreshToken!);

      // Update stored credentials (Microsoft may rotate refresh tokens)
      await this.save(source, {
        ...cred,
        value: result.accessToken,
        refreshToken: result.refreshToken || cred.refreshToken,
        expiresAt: result.expiresAt,
      });

      debug(`[SourceCredentialManager] Refreshed Microsoft token for ${source.config.slug}`);
      return result.accessToken;
    } catch (error) {
      const errorMsg = error instanceof Error ? error.message : String(error);
      debug(`[SourceCredentialManager] Microsoft token refresh failed:`, error);
      this.markSourceNeedsReauth(source, `Token refresh failed: ${errorMsg}`);
      return null;
    }
  }

  /**
   * Refresh MCP OAuth token