refactor(featureset): thread &'static FeatureSet instead of Arc

[varex83agent]

Closes #616

FeatureSet is resolved exactly once — after the cluster lock's fork version feeds the gnosis hotfix — and never mutated, so it lives for the whole process. This replaces the Arc<FeatureSet> threading with a Copy &'static FeatureSet obtained by leaking once at the resolution point.

Changes

• Resolution point (node/mod.rs): let feature_set: &'static FeatureSet = Box::leak(Box::new(resolve_feature_set(...)?));. All three Arc::clones threading it into the consensus controller, p2p behaviour, and core workflow are dropped (&'static is Copy).
• Fields drop the Arc: ConsensusController::Config, qbft::Consensus + its Config, TrackerService, InclusionCore, InclusionChecker, WireInputs, WireP2PParams.
• Timers: get_round_timer_func and the three with_duty constructors take &'static FeatureSet. The new()/Default paths no longer allocate a throwaway FeatureSet::new() — the field is now Option<&'static FeatureSet> (None until bound to a duty, which is the only reader via the round-one proposal-timeout override).
• Single convention: the second &FeatureSet convention in tracker/analysis.rs (9 signatures) and infosync is collapsed onto &'static FeatureSet.
• Derived set: tracker_feature_set (wire.rs) leaks its own small masked static instead of deep-cloning the whole set into a second Arc.
• Docs: the featureset crate module doc now mandates the &'static convention (leak once at startup).
• Tests: each construct and leak their own set (Box::leak(Box::new(...))), equally cheap per the issue.

Acceptance

• No Arc<FeatureSet> in the workspace:

  $ rg 'Arc<FeatureSet>' crates/
  (no matches)
  

• No FeatureSet::new() throwaway allocations for filling fields (timers use Option<&'static> = None).
• Single passing convention (&'static FeatureSet).
• The #[allow(clippy::too_many_arguments)] on Tracker::start is retained: even without feature_set, start has 8 parameters, so clippy still requires it (clippy -D warnings passes with it in place).

Verification (all pass)

• cargo build --workspace --all-features
• cargo +nightly fmt --all
• cargo clippy --workspace --all-targets --all-features -- -D warnings
• cargo test for touched crates (pluto-featureset, pluto-consensus, pluto-core, pluto-infosync, pluto-app) — all green, including the wiring.rs Tier-1 tests.

🤖 Generated with Claude Code

[emlautarom1]

Could you please fix the conflicts and merge main?

[emlautarom1]

Could you please fix the conflicts and merge main?

@varex83

[emlautarom1]

LGTM, no semantic changes. Before merging check if we can remove explicit 'static annotations (run your agent against the diff and make it check).

[emlautarom1]

In general, the're are multiple places where we can drop the specific 'static lifetime annotation. This is one case, and by dropping it we can remove the need for this function altogether. Check for all signatures with 'static and see if we can drop it.

[varex83agent]

Done in a932bf7. I let the compiler decide: stripped 'static from every &FeatureSet occurrence in the workspace, then added it back one error at a time until it compiled. What the borrow checker actually requires is only struct fields, the constructors that feed them, and the timer closures get_round_timer_func builds.

Dropped from: the eight tracker::analysis functions (including this one), infosync::Component::new, and wire::tracker_feature_set (now elided, tying the derived set's lifetime to the input). A &'static FeatureSet coerces on the way in, so no caller changed.

And yes — default_feature_set() is gone; the tests borrow a local &FeatureSet::new(). I also recorded the narrowed rule in the featureset module doc so it doesn't drift back: spell 'static out only where the reference is stored.

[emlautarom1]

We could try to merge this field with the duty since they're both either None or Some at the same time. Not major, but removes the need for comments and an implicit dependency.

[varex83agent]

Merged in a932bf7. All three timers now hold a single duty: Option<BoundDuty>:

struct BoundDuty {
    duty: Duty,
    feature_set: &'static FeatureSet,
}

The implicit dependency and both explanatory comments are gone, and proposal_timeout_duration drops a parameter along with its is_some_and dance:

fn proposal_timeout_duration(bound: Option<&BoundDuty>, round: i64) -> Option<Duration> {
    let bound = bound?;
    if round == 1 && is_proposer(&bound.duty) && bound.feature_set.enabled(Feature::ProposalTimeout)