feat: add sky liquidity venue

[Jean-Grimal]

Fixes https://linear.app/morpho-labs/issue/SDK-109/morp2-44medium-sky-token-fallback-liquidations-convert-into-daimkr-but

[linear]

SDK-109

[Foulks-Plb]

@codex review

[Rubilmax]

@prd-carapulse[bot] review this PR, focusing on security of the liquidation bot and controller wallet as well as on edge cases related to sky liquidity and markets

[prd-carapulse]

API call failed after 3 retries: You exceeded your current quota, please check your plan and billing details. For more information on this error, read the docs: https://platform.openai.com/docs/guides/error-codes/api-errors.

Track: https://carapulse.morpho.dev/dashboard/runs?run_id=gw_run_5543923974e6

[Rubilmax]

@prd-carapulse[bot] review this PR, focusing on security of the liquidation bot and controller wallet as well as on edge cases related to sky liquidity and markets

[prd-carapulse]

Review posted: #104 (comment)

Result:

• No blocking security findings.
• Controller wallet not newly exposed.
• Sky converter routes look correct.
• pnpm build passed.
• Focused fork test inconclusive due local Anvil/Foundry RPC-chain issue; direct mainnet RPC checks passed.
• No code PR opened; only optional hardening noted.

Track: https://carapulse.morpho.dev/dashboard/runs?run_id=gw_run_700b694c9cd9

[prd-carapulse]

Review complete — no blocking security findings.

• Controller wallet exposure: no new arbitrary calldata path. Sky converter calls are fixed selectors to configured mainnet converter addresses, value = 0, and converted assets return to encoder.address, not the controller EOA.
• Approvals: DAI/USDS exact approval is consumed by transferFrom. MKR/SKY approval is redundant because MkrSky burns msg.sender directly; it may leave a stale exact allowance to the immutable converter, but I do not see an exploitable spend path.
• Sky route edge cases: USDS/SKY preferAlternative chaining looks correct (USDS/SKY -> DAI/MKR -> downstream venue), direct pairs stop when src === dst, and mainnet-only config is respected.
• On-chain sanity: mainnet RPC shows both converters have code; MkrSky.rate() returns 24000.

Verification:

• pnpm build passed.
• Focused fork test was inconclusive in this runtime: local Anvil/Foundry forked Base despite a mainnet fork URL, so MkrSky.rate() returned no data there. Direct mainnet RPC checks above passed.

Optional hardening: remove the redundant MKR/SKY approval and add tests for MKR -> SKY, non-multiple SKY dust rounding, and full preferAlternative chaining into a downstream venue.