Add WalletConnect support to Blockdaemon Institutional Vault

[MnrGreg]

Type of submission

• New wallet application
• Update to an existing wallet's feature support
• Third-party verification (confirmed, or disputed as unsupported) of an existing claim
• Marking a feature as not supported, with a reason

Summary

Self-attest WalletConnect for Blockdaemon Institutional Vault. The listing now claims walletconnect_support with screenshots of a Vault Canton WalletConnect session and the same bd:: party connected in DA Registry (Test).

Checklist

• wallets/<wallet-name>.yaml added or updated (self-attestation)
• A heading added to proofs/<wallet-name>/<wallet-name>-self-attestation.md
  for every feature newly claimed as supported: true
• python scripts/generate_table.py was run and the regenerated
  WALLET_DIRECTORY.md is included in this PR (a CI check will catch
  this if it's missed, but running it locally saves a round trip)
• If applying for the first time: confirmed membership in
  #ext-temp-party-scaling and set slack_party_scaling_channel_joined: true
  (already set on the existing listing from Add Blockdaemon Institutional Vault to the wallet directory #12)
• If marking a feature as not supported: reason filled in under that
  feature's reason: field, not just left blank
• If this is a verification: the heading added to
  proofs/<wallet-name>/<wallet-name>-third-party-attestation.md
  reflects evidence gathered independently, not copied from the
  wallet's self-attestation, and result on the matching
  verified_by entry is set to verified or unsupported to match

Additional context

Evidence is connection and party identity (no dApp-initiated on-chain update ID attached):

• Vault UI: WalletConnect is on for Canton, connected dApp Canton dApp
• Vault Addresses: Canton main address bd::122075956b9…
• DA Registry Test (registry.test.app.digitalasset.com/registry/onboarding): connected Wallet / Provider party bd::122075956b920f8d6786f4872515e900d7920c19c5c57647d434fc62b5c5229913bf, User ID bd

Public docs: WalletConnect Usage, IV v3.7.0 changelog.

Follows Add Blockdaemon Institutional Vault to the wallet directory (#12).