docs: add caveat to lsig off-curve account generation

Wallets can advertise each account's empty signature (the signature fields
of a SignedTransaction, base64 msgpack without `txn`) so dApps know the
account type and can simulate with correctly-shaped signatures for fees.

- WalletAccount.emptySignature, plus encode/decode/getSignatureType helpers
- emptyTransactionSigner on wallets, the manager and all framework hooks
- Manager checks empty signatures against algod's auth address on connect,
  resume and network change, and clears them when an account was rekeyed
- signData throws for PQ accounts until ARC-60 supports them
- WalletConnect reads empty signatures from scopedProperties on approval
- Raise the algosdk peer floor to ^3.7.0 for pqsig support

The hardcoded "^5.0.0" peer range excludes prerelease versions, so
installing prerelease adapters alongside prerelease core (e.g. 5.1.0-next.1
from the next channel) fails with ERESOLVE under npm. workspace:^ is
rewritten at publish to ^<version>: ^5.1.0-next.1 for prereleases and
^5.1.0 for stable releases, matching how lockstep versioning ships them.

The hardcoded "^5.0.0" peer range excludes prerelease versions, so
installing prerelease adapters alongside prerelease core (e.g. 5.1.0-next.1
from the next channel) fails with ERESOLVE under npm. workspace:^ is
rewritten at publish to ^<version>: ^5.1.0-next.1 for prereleases and
^5.1.0 for stable releases, matching how lockstep versioning ships them.

Pushes to next publish prerelease versions (e.g. 5.1.0-next.N) to the next
npm dist-tag, and CI runs on pull requests into next. publish-packages.mjs
already tags prerelease versions as next, and Discord announcements already
skip prereleases.

Pushes to next publish prerelease versions (e.g. 5.1.0-next.N) to the next
npm dist-tag, and CI runs on pull requests into next. publish-packages.mjs
already tags prerelease versions as next, and Discord announcements already
skip prereleases.