feat: add includeClaimable query param to vesting-info endpoints

[TarikGul]

Adds optional vesting calculation fields to /accounts/{accountId}/vesting-info and
/rc/accounts/{address}/vesting-info endpoints.

Usage

GET /accounts/{address}/vesting-info?includeClaimable=true

New response fields (when includeClaimable=true)

• vested (per schedule) - Amount vested based on time elapsed
• vestedBalance - Total vested across all schedules
• vestingTotal - Total locked across all schedules
• vestedClaimable - Actual claimable amount (accounts for already claimed tokens)
• blockNumberForCalculation - Block number used for calculation
• blockNumberSource - 'relay' or 'self'

Example response

{
  "at": { "hash": "0x...", "height": "12345" },
  "vesting": [
    {
      "locked": "1000000000000",
      "perBlock": "1000000",
      "startingBlock": "1000",
      "vested": "500000000000"
    }
  ],
  "vestedBalance": "500000000000",
  "vestingTotal": "1000000000000",
  "vestedClaimable": "500000000000",
  "blockNumberForCalculation": "501000",
  "blockNumberSource": "relay"
}

Migration behavior

Vesting migrated from relay chains to Asset Hub. The calculation logic varies based on chain type and migration
state:

Vesting migrated from relay chains to Asset Hub. The calculation logic varies based on chain type and migration
state:

Chain	Migration State	Behavior
Relay Chain	Pre-migration	Uses relay chain's own block number (blockNumberSource: 'self')
Relay Chain	During migration	Returns vestedClaimable: '0' (claims paused)
Relay Chain	Post-migration	Returns vestedClaimable: '0' (vesting moved to Asset Hub)
Asset Hub	Pre-migration	Returns raw vesting data only (no calculations)
Asset Hub	During migration	Returns vestedClaimable: '0' (claims paused)
Asset Hub	Post-migration	Uses relay chain inclusion block number (blockNumberSource: 'relay'). Requires
relay chain connection via SAS_SUBSTRATE_MULTI_CHAIN_URL.

Note

This PR also abstracts the relay chain block search logic to make it more modular and reusable across different
services.

[bee344]

@TarikGul Shouldn't the openapi docs be updated as well?

[TarikGul]

@TarikGul Shouldn't the openapi docs be updated as well?

Yup perfect timing, just pushed them up :)

[bee344]

Just a couple of unnecesary descriptions in the docs, other than that it looks solid.