AlgoScan

Crate:
- arc89: validate metadata size at the decode() boundary (reject > MAX_METADATA_SIZE);
  normalize the short-metadata identifier bit in compute_hash/set_hash so the
  hash always reflects the body size per ARC-89; expand the method-constant set
  to the full registry interface.
- asa: NftMint::fractional now validates decimals in 1..=19 (returns
  InvalidFractionalDecimals) — fixes the 10u64.pow overflow and the decimals=0
  inconsistency with is_fractional_nft.
- url: encapsulate Cid (private fields + v0/v1 constructors + accessors) so an
  invalid CIDv0 codec state is unrepresentable; return UnsupportedCid (not
  MalformedCid) for unsupported v1 multicodecs.
- royalty: clamp royalty_basis to MAX_BASIS_POINTS (10000) in royalty_for to
  prevent u128->u64 truncation; add the constant.
- arc69: require `standard` on the wire (drop the serde default) so a note that
  omits it is rejected by from_note.
- indexer: give Arc74Client a 30s default request timeout (+ with_timeout).

Docs:
- ADR: sync the D2 feature example with the shipped manifest (only `fetch`);
  add a language to the D3 fenced block (markdownlint MD040); fix the
  self-contradicting "Status is Proposed" line under an accepted ADR.

examples/nft/mint_arc19: use Cid::v1 for the encapsulated constructor.

The examples/nft/* programs require `["nft", "algod"]`; with `nft` off by
default, the default clippy/check/test runs skipped them. Add `--features
nft` to the steps that compile examples:

- Makefile: `clippy` and `test` targets (so `make ci` builds and lints them).
- CI (general.yml): `cargo-check`, `cargo-clippy`, `cargo-test` jobs.

`nft` is additive (default-off), so enabling it on the --all-targets /
--examples steps is strictly more coverage and cannot mask a default-build
breakage. The wasm-check job stays default.

Organize every example under examples/<category>/ — client, contract,
app, asset, transaction, account, logic_sig, wallet, nft — with explicit
[[example]] path entries. The example `name` is unchanged, so
`cargo run --example <name>` keeps working.

Move the NFT examples out of algonaut_nft/examples and into examples/nft,
and rewrite them against a live algod instead of mocking: real
suggested_params, submit, and real asset ids returned from the network
(no DemoParams stub, no hardcoded AssetId). Gated on
required-features = ["nft", "algod"]:
- nft_mint_arc3   — pure NFT, ARC-3 off-chain metadata
- nft_mint_arc19  — mutable NFT; mint then UpdateAsset the reserve
- nft_mint_arc69  — on-chain metadata in the acfg note
- nft_soulbound   — full ARC-71 issue/hold/revoke across issuer + funded holder
- nft_arc89_box   — mint for a real id, build the ARC-89 box offline

Redesign the asa module around a fluent NftMint builder and make the
crate's API idiomatic, then add runnable examples that lead the UX.

asa:
- Replace the leaky create_pure_nft / create_fractional_nft free
  functions (which returned a half-built CreateAsset and told the caller
  via doc comment to attach url/hash/reserve themselves) with NftMint.
  NftMint::pure/fractional own the configuration; .arc3() computes the
  ARC-3 metadata hash and appends #arc3, .arc19() derives the reserve
  from a CID, .arc69() places metadata in the note. Terminals return a
  finished CreateAsset (into_create) or Transaction (build).
- Make the NFT-shape predicates an extension trait (NftShape) so they
  read as methods on AssetParams.
- Rework the ARC-71 Soulbound typestate so Held/Revoked carry the
  AssetId; claim/revoke are now total (no Option, no unwrap).

url: Cid and TemplateIpfsUrl gain Display / FromStr; reserve derivation
is now `impl From<Cid> for Address`; the free parse/render/convert
functions become methods.

arc89: add with_* flag setters so callers never poke raw flag bytes.

lib: ZERO_ADDRESS is a const (was a fn); add a curated prelude.

examples/: mint_pure_nft, mint_mutable_arc19, mint_onchain_arc69,
soulbound_credential, resolve_metadata, arc89_preview — each builds and
runs, demonstrating the new ergonomics end to end.

No backward-compat concerns: the crate is unreleased.