feat: add multi theme support

[evavirseda]

Description of change

Add multi theme

Recommended configurations after this PR

Shimmer EVM

[
    {
        "id": 0,
        "text": "ShimmerEVM",
        "apiEndpoint": "https://api.shimmer.network",
        "chainAddress": "smr1prxvwqvwf7nru5q5xvh5thwg54zsm2y4wfnk6yk56hj3exxkg92mx20wl3s",
        "chainID": 148,
        "blockExplorer": "https://explorer.evm.shimmer.network",
        "networkUrl": "https://json-rpc.evm.shimmer.network",
        "chainRef": "shimmer-evm"
    },
    {
        "id": 1,
        "text": "Custom Network",
        "apiEndpoint": "http://localhost:14265",
        "faucetEndpoint": "http://localhost:8091",
        "chainAddress": "tst1pz0kc4urqxf4vh6c556gnr6uwmkwz5ye98vucakgafyneed4gft322s3gf0",
        "chainID": 1074,
        "blockExplorer": "",
        "networkUrl": "",
        "chainRef": "shimmer-evm"
    }
]

Shimmer EVM Testnet

[
    {
        "id": 0,
        "text": "ShimmerEVM (Testnet)",
        "apiEndpoint": "https://evm-toolkit-api.testnet.shimmer.network",
        "faucetEndpoint": "https://faucet.testnet.shimmer.network",
        "chainAddress": "rms1ppp00k5mmd2m8my8ukkp58nd3rskw6rx8l09aj35984k74uuc5u2cywn3ex",
        "chainID": 1073,
        "blockExplorer": "https://explorer.evm.testnet.shimmer.network",
        "networkUrl": "https://json-rpc.evm.testnet.shimmer.network",
        "chainRef": "shimmer-evm-testnet"
    },
    {
        "id": 1,
        "text": "Custom Network",
        "apiEndpoint": "http://localhost:14265",
        "faucetEndpoint": "http://localhost:8091",
        "chainAddress": "tst1pz0kc4urqxf4vh6c556gnr6uwmkwz5ye98vucakgafyneed4gft322s3gf0",
        "chainID": 1074,
        "blockExplorer": "",
        "networkUrl": "",
        "chainRef": "shimmer-evm-testnet"
    }
]

Links to any relevant issues

Closes #32

Type of change

• Bug fix (a non-breaking change which fixes an issue)
• Enhancement (a non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Fix

How the change has been tested

Change checklist

• [ ] I have followed the contribution guidelines for this project
• [ ] I have performed a self-review of my own code
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] I have checked that new and existing unit tests pass locally with my changes
• [ ] I have updated the CHANGELOG.md, if my changes are significant enough