Swap: Get Prices for Third Party SNS tokens

[joel-medicala-yral]

• Currently in #447 we are only getting the prices for YRAL SNS tokens by querying the token prices from the token creator's canister
• Add support for lookups for third party SNS tokens and cks by getting their prices from third party sources etc...

Flow

flowchart TD
    Caller[Caller args:token_ledger] --> get_token_price[Get Token Price] --> |Checks token value from third-party sources tbd icpswap as placeholder| ThirdPartySources{Third Party Sources}

    ThirdPartySources --> |Price Available| Available[Available] --> return[Return Token Price]
    ThirdPartySources --> |Price Unavailable| Unavailable[Unavailable] --> |Fallback| get_ledger_controllers[Get Ledger Controllers] --> filter_canister_ids[Filter Canister IDs]

    filter_canister_ids --> |Verifies token ownership by calling deployed CDAO for each ID| IsTokenOwner{Is Token Owner?}

    IsTokenOwner --> |Not Owner| NotOwner[Error: Not Owner] --> error[Error]
    IsTokenOwner --> |Owner Verified| Owner[Owner] --> check_price_field[Check Price Field] --> return[Return Token Price]