feat: add OpenShift AI inference provider

[jeffmaury]

Fixes #326

[benoitf]

LGTM. not tested but it won't break anything

[simonrey1]

suggestion: introduce intermediate method to avoid doing split then map on the same separator

    private async getTokens(): Promise<string[]> {
    // get raw string from secret storage
    let raw: string | undefined;
    try {
      raw = await this.secrets.get(TOKENS_KEY);
    } catch (err: unknown) {
      console.error('OpenShift AI: something went wrong while trying to get tokens from secret storage', err);
    }
    // if undefined return empty array
    if (!raw) return [];
    // split raw string by token separator
    return raw.split(TOKEN_SEPARATOR)
  }

  /**
   * Get all connection infos from secret storage
   * @private
   */
  private async getConnectionInfos(): Promise<ConnectionInfo[]> {
    return (await this.getTokens()).map(str => {
      const [token, baseURL] = str.split(INFO_SEPARATOR);
      return {
        token,
        baseURL,
      };
    });
  }

  /**
   * Save connection info to secret storage
   * @param token
   * @param baseURL
   * @private
   */
  private async saveConnectionInfo(token: string, baseURL: string): Promise<void> {
    // get existing tokens
    const tokens = await this.getTokens();
    // concat new token with existing tokens
    const raw = [...tokens, `${token}${INFO_SEPARATOR}${baseURL}`].join(TOKEN_SEPARATOR);
    // save to secret storage
    await this.secrets.store(TOKENS_KEY, raw);
  }

  private async removeConnectionInfo(token: string, baseURL: string): Promise<void> {
    const connectionInfos = await this.getConnectionInfos();
    // filter out the token
    const raw = connectionInfos.filter(t => t.token !== token || t.baseURL !== baseURL).join(TOKEN_SEPARATOR);
    // save to secret storage
    await this.secrets.store(TOKENS_KEY, raw);
  }

[simonrey1]

LGTM, not tested