Feat/add stellar bridge controller

[Julink-eth]

Explanation

Adds Stellar support to @metamask/bridge-controller, following the existing non-EVM patterns for Solana, Bitcoin, and Tron. This includes Stellar chain/native asset constants, CAIP formatting, default token metadata, quote validation, non-EVM fee handling via snap computeFee, and targeted test coverage.
Also aligns Stellar asset formatting with the Bridge API contract:

• Native XLM: stellar:pubnet/slip44:148
• Classic assets: stellar:pubnet/asset:CODE-ISSUER
• Soroban contracts: stellar:pubnet/sep41:C...

References

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've communicated my changes to consumers by updating changelogs for packages I've changed
• I've introduced breaking changes in this PR and have prepared draft pull requests for clients and consumer packages to resolve them

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Note

Medium Risk
Adds a new non-EVM chain path (Stellar) across chain-id/asset formatting, validation, and snap-based fee computation; regressions could impact quote requests or fee display for non-EVM chains. Changes are mostly additive with tests, limiting blast radius but touching shared chain-id utilities.

Overview
Adds Stellar network support to @metamask/bridge-controller, including a new ChainId.STELLAR, XlmScope.Pubnet being treated as an allowed bridge chain, and default native token metadata for XLM (decimals/slip44 mapping).

Extends shared utilities to recognize Stellar via isStellarChainId, treat it as non-EVM in isNonEvmChainId, and format Stellar chain IDs/asset IDs in caip-formatters (native stellar:pubnet/slip44:148, classic asset:CODE-ISSUER, and Soroban sep41:C…).

Updates quote request validation to require destWalletAddress when bridging to/from Stellar, exports isStellarChainId, and adds targeted tests (including verifying Stellar quotes get nonEvmFeesInNative via snap computeFee calls).

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