docs: replace Mintscan explorer links with Seistream - #48

Running Vale across on the following files affected by this PR:

- STYLE_GUIDE.md
- cosmos-sdk/index.mdx
- evm/differences-with-ethereum.mdx
- evm/precompiles/cosmwasm-precompiles/cosmwasm.mdx
- evm/precompiles/cosmwasm-precompiles/example-usage.mdx
- learn/dev-interoperability.mdx
- learn/dev-token-standards.mdx
- learn/explorers.mdx
- learn/pointers.mdx
- learn/sip-03-migration.mdx

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STYLE_GUIDE.md:
	- 1:3       Use sentence case for headings: 'Sei Docs Style Guide'.
	- 9:5       Use sentence case for headings: 'Beginner Friendly'.
	- 25:41     'quite' is often unnecessary qualifying language — consider removing it.
	- 25:57     'completely' is often unnecessary qualifying language — consider removing it.
	- 26:25     'simply' is often unnecessary qualifying language — consider removing it.
	- 67:5      Use sentence case for headings: 'Cosmos-SDK (Deprecated)'.
	- 73:5      Use sentence case for headings: 'Operate (Node)'.
	- 82:4      Use sentence case for headings: 'Style Guidelines'.
	- 84:5      Use sentence case for headings: 'Acronyms and Abbreviations'.
	- 90:177    'very' is often unnecessary qualifying language — consider removing it.
	- 255:5     Use sentence case for headings: 'Callouts and Admonitions'.

evm/differences-with-ethereum.mdx:
	- 53:4     Use sentence case for headings: 'Sei EVM Release'.
	- 69:4     Use sentence case for headings: 'Opcode Differences'.
	- 83:5     Use sentence case for headings: 'PREVRANDAO'.
	- 97:4     Use sentence case for headings: 'State Root'.
	- 104:4    Use sentence case for headings: 'Block Hash'.
	- 109:4    Use sentence case for headings: 'Base Fee & Tips'.
	- 134:4    Use sentence case for headings: 'Non-EVM Transactions'.
	- 148:4    Use sentence case for headings: 'Pending State'.
	- 159:4    Use sentence case for headings: 'Gas Model & Fees'.
	- 181:4    Use sentence case for headings: 'SSTORE Gas Cost'.
	- 195:4    Use sentence case for headings: 'ERC Token Standards Compatibility'.
	- 205:4    Use sentence case for headings: 'Testing & Migration Checklist'.

evm/precompiles/cosmwasm-precompiles/cosmwasm.mdx:
	- 23:4     Use sentence case for headings: 'How Does the CosmWasm Precompile Work?'.
	- 31:4     Use sentence case for headings: 'What You'll Learn in This Guide'.
	- 44:5     Use sentence case for headings: 'Transaction Functions'.
	- 74:5     Use sentence case for headings: 'Query Functions'.
	- 87:4     Use sentence case for headings: 'Using the Precompile'.
	- 100:6    Use sentence case for headings: 'Install Dependencies'.
	- 112:6    Use sentence case for headings: 'Import Precompile Components'.
	- 137:4    Use sentence case for headings: 'Critical: Understanding Message Formats'.
	- 141:5    Use sentence case for headings: 'CosmWasm Message Structure'.
	- 151:5    Use sentence case for headings: 'How Message Encoding Works'.
	- 163:5    Use sentence case for headings: 'Best Practice: Message Encoding Helpers'.
	- 206:4    Use sentence case for headings: 'Message Format Helpers'.
	- 254:4    Use sentence case for headings: 'Step-by-Step Guide: Using the CosmWasm Precompile'.
	- 256:5    Use sentence case for headings: 'Execute a CosmWasm Contract'.
	- 314:5    Use sentence case for headings: 'Execute Batch Operations'.
	- 385:5    Use sentence case for headings: 'Query a CosmWasm Contract'.
	- 454:4    Use sentence case for headings: 'Advanced Usage Examples'.
	- 456:5    Use sentence case for headings: 'Cross-Runtime DeFi Integration'.
	- 495:5    Use sentence case for headings: 'Complete Integration Example'.
	- 733:5    Use sentence case for headings: 'Common Issues and Solutions'.
	- 735:6    Use sentence case for headings: 'Message Encoding Issues'.
	- 753:5    Use sentence case for headings: 'Error Code Reference'.
	- 764:4    Use sentence case for headings: 'Important Notes'.
	- 768:5    Use sentence case for headings: 'Message Format Requirements'.
	- 774:5    Use sentence case for headings: 'Contract Address Format'.
	- 780:5    Use sentence case for headings: 'Cross-Runtime Considerations'.
	- 788:5    Use sentence case for headings: 'Best Practices'.

evm/precompiles/cosmwasm-precompiles/example-usage.mdx:
	- 50:6    Use sentence case for headings: 'Querying & Executing a CosmWasm Contract'.

learn/dev-interoperability.mdx:
	- 12:4    Use sentence case for headings: 'Dual Address Support'.
	- 26:4    Use sentence case for headings: 'Virtual Machine Interoperability'.
	- 38:4    Use sentence case for headings: 'Precompile Contracts'.
	- 46:4    Use sentence case for headings: 'Example Diagram'.

learn/dev-token-standards.mdx:
	- 20:4    Use sentence case for headings: 'Sei Token'.
	- 45:4    Use sentence case for headings: 'Fungible Tokens'.
	- 50:5    Use sentence case for headings: 'Smart Contract Tokens'.

learn/explorers.mdx:
	- 7:4     Use sentence case for headings: 'What Is a Block Explorer?'.
	- 39:4    Use sentence case for headings: 'Sei Explorers'.

learn/pointers.mdx:
	- 17:4    Use sentence case for headings: 'Why Pointer Contracts'.
	- 34:4    Use sentence case for headings: 'How Pointer Contracts Work'.

learn/sip-03-migration.mdx:
	- 42:4     Use sentence case for headings: 'IBC Asset Migration Table'.
	- 68:5     Use sentence case for headings: '1) Asset Transfer (Native ↔ EVM)'.
	- 77:5     Use sentence case for headings: '2) USDC on Sei'.
	- 102:5    Use sentence case for headings: '3) Address Association (Seistream)'.
	- 182:4    Use sentence case for headings: 'FAQ'.
	- 214:5    Use sentence case for headings: 'I hold USDC.n (USDC via Noble) — what should I do?'.


Found 68 suggested changes across 9 files in 1002.71ms