fix(p2p): give each underlay address fresh 15s connection timeout

[gacevicljubisa]

Checklist

• I have read the coding guide.
• My change requires a documentation update, and I have done it.
• I have added tests to cover my changes.
• I have filled out the description and linked the related issues.

Description

• Give each underlay address a dedicated 15-second connection timeout
• Prevents later addresses from being starved of connection time
• Increase kademlia's total peer connection timeout from 15s to 45s to accommodate multiple address attempts
• Each bootnode connection attempt now gets the full 45s budget

Previously, when connecting to a peer with multiple underlay addresses, all addresses shared a single timeout context. This meant later addresses had little to no time remaining for connection attempts. Now each address receives its own fresh 15-second timeout, ensuring fair connection attempts to all underlay addresses.

In kademlia's bootnode connection logic, the global 15-second timeout has been removed and replaced with a per-connection 45-second timeout, allowing multiple addresses per peer to be tried sequentially with adequate time budget.

Open API Spec Version Changes (if applicable)

Motivation and Context (Optional)

Related Issue (Optional)

Screenshots (if appropriate):

[janos]

Looks ok.