Refactor: bundle Prove::prove and AppRunner::run_all inputs into a struct

[imikushin]

Follow-up from PR #170 (versioned apps).

After versioned apps landed, Prove::prove and AppRunner::run_all each take 5+ map-shaped parameters, several of which have similar generic key types (B32, App). The current signatures:

fn prove(
    &self,
    norm_spell: NormalizedSpell,
    app_binaries: BTreeMap<B32, Vec<u8>>,
    app_signatures: BTreeMap<B32, AppSignature>,
    app_private_inputs: BTreeMap<App, Data>,
    prev_txs: Vec<Tx>,
    tx_ins_beamed_source_utxos: BTreeMap<usize, BeamSource>,
) -> anyhow::Result<(NormalizedSpell, Proof, u64)>;

pub fn run_all(
    &self,
    app_binaries: &BTreeMap<B32, Vec<u8>>,
    versioned_apps: &BTreeMap<B32, VersionedApp>,
    app_signatures: &BTreeMap<B32, AppSignature>,
    tx: &Transaction,
    app_public_inputs: &BTreeMap<App, Data>,
    app_private_inputs: &BTreeMap<App, Data>,
) -> Result<Vec<u64>>;

This is hard to read at call sites and easy to get wrong if more inputs are added later. Bundle them into a dedicated inputs struct (or two — one per function), e.g.:

pub struct AppRunInputs<'a> {
    pub app_binaries: &'a BTreeMap<B32, Vec<u8>>,
    pub versioned_apps: &'a BTreeMap<B32, VersionedApp>,
    pub app_signatures: &'a BTreeMap<B32, AppSignature>,
    pub app_public_inputs: &'a BTreeMap<App, Data>,
    pub app_private_inputs: &'a BTreeMap<App, Data>,
}

impl AppRunner {
    pub fn run_all(&self, inputs: &AppRunInputs<'_>, tx: &Transaction) -> Result<Vec<u64>> { ... }
}

Notes:

• Prove is pub, but in v15 there are no external implementors — this is still a breaking change semantically; should land in a minor version bump, with a brief changelog note.
• AppInput already exists in charms-data and may be the right place to hang most of the new bundle (it already holds app_binaries, app_private_inputs, app_signatures).

Referenced in PR #170 review comments:

• Versioned Apps #170 (comment) (Prove trait)
• Versioned Apps #170 (comment) (run_all)

[imikushin]

Adding a perf-related angle to the same refactor:

While addressing the check_app_version_continuity perf concern (now fixed in dba1d68), I noticed that is_simple_transfer is still called once per spending app in each of:

• check_app_version_continuity (after the hoist),
• AppRunner::run_all (per-app loop),
• is_correct's None branch (apps.iter().all(...)).

In any single is_correct invocation, that's 2x per app. The natural fix is to compute simple_transfer_apps: BTreeSet<App> once at the top of is_correct after to_tx and pass it everywhere downstream — which means another parameter on Prove::prove and AppRunner::run_all.

Since this issue already proposes bundling those signatures into an AppRunInputs-shaped struct, the precomputed simple_transfer_apps should ride along inside the same struct. Folding it in here so it gets done in one pass.

Inside the zkVM the saving is at most a 2x factor on is_simple_transfer work — sub-1% of total proof cycles in typical spells, but free if we're refactoring the signatures anyway.