feat(docs): Agent Skills registry + Templates gallery - #36

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

- .mintlify/skills/sei-contracts/SKILL.md
- .mintlify/skills/sei-frontend/SKILL.md
- .mintlify/skills/sei-nodes/SKILL.md
- .mintlify/skills/sei-payments/SKILL.md
- .mintlify/skills/sei-precompiles/SKILL.md
- .mintlify/skills/sei-security/SKILL.md
- ai/skills.mdx
- evm/templates.mdx

Attempting to initialize Vale linter...
Customer vale configuration detected. Attempting to sync packages...
Packages synced successfully.
Attempting to run Vale spellcheck...
Vale spellcheck completed successfully.

.mintlify/skills/sei-contracts/SKILL.md:
	- 225:4    Use sentence case for headings: 'Account abstraction (ERC-4337)'.

.mintlify/skills/sei-frontend/SKILL.md:
	- 143:5    Use sentence case for headings: 'Sei Global Wallet (embedded, social login)'.
	- 156:9    Use sentence case for headings: 'Dual-address UX ( *** ↔ ***** )'.

.mintlify/skills/sei-payments/SKILL.md:
	- 42:4    Use sentence case for headings: 'Send / accept USDC (viem)'.

.mintlify/skills/sei-precompiles/SKILL.md:
	- 56:4     Use sentence case for headings: 'Reading state (Bank, viem)'.
	- 82:4     Use sentence case for headings: 'Staking + Distribution (ethers v6)'.
	- 211:4    Use sentence case for headings: 'Address association (Addr precompile)'.
	- 224:4    Use sentence case for headings: 'Cross-VM: Pointer / PointerView'.


Found 8 suggested changes across 4 files in 912.19ms