Feat/auth snapshot

[Power70]

Per-Entrypoint Auth Snapshot Test

Closes #829

Summary

Adds an integration suite that snapshots the Soroban authorization required by every
state-changing entrypoint of PredictifyHybrid. Rather than only asserting "authorized
succeeds / unauthorized fails", each test inspects env.auths() after the call and pins
which address the host actually required an authorization from.

This catches two regressions a pass/fail test misses: a require_auth silently dropped
(auth set becomes empty), and an auth subject rebound to the wrong argument.

Writing the suite surfaced three real authorization defects and a set of pre-existing build
breakages that stopped the crate compiling at all. Both are fixed here so the suite can run.

Changes

Tests

• tests/auth_snapshot.rs (new) — 24 tests: committed-snapshot assertions for 13
  entrypoints, auth-boundary assertions for 3, read-only entrypoints pinned to no auth,
  plus edge cases (wrong-subject binding, subject tracking across users, non-admin
  rejection, #[should_panic] no-auth traps). The fixture registers a real Stellar Asset
  Contract so stake transfers commit.
• Cargo.toml — registered the auth_snapshot test target.

Authorization fixes

Soroban rejects a second require_auth on an already-authorized frame
(Error(Auth, ExistingValue)). Three paths authorized the same address twice — entrypoint
and inner manager — so they could never succeed on-chain:

• fees.rs — redundant admin.require_auth() in FeeManager::collect_fees. It was
  #[cfg(not(test))]-gated, so unit tests masked it while production builds hit it.
• disputes.rs — redundant user.require_auth() in DisputeManager::dispute_market.
• rate_limiter.rs — redundant user.require_auth() in rate_limit_voting /
  rate_limit_disputes.

Auth strength is unchanged: each is still enforced by the calling entrypoint
(require_primary_admin for admin paths, user.require_auth() for user paths).

Build restoration

The crate did not compile on master: e5db2d8 collapsed lib.rs to a "minimal working
version" and later PRs re-added call sites without restoring their definitions.

• lib.rs — restored 14 dropped mod declarations; the initialize / deposit /
  withdraw / get_balance entrypoints; the admin-auth helpers (stored_primary_admin,
  require_primary_admin{,_or_panic}, require_initialized_admin_root,
  require_admin_permission); the SYM_* / PERCENTAGE_DENOMINATOR constants and the
  resolution_timeout_reached / automatic_oracle_result_unavailable helpers. Removed
  duplicate imports, fixed 7 invalid Address derefs, repointed capabilities().
• resolution.rs — repaired a mis-merge that spliced a payout-distribution body into
  impl ResolutionOutcomeCache and into determine_outcome_from_oracle_data; restored the
  cache methods 6 modules call, ResolutionAnalytics / MedianResolutionResult, and the
  OracleResolutionManager impl boundary.
• market_id_generator.rs — restored the clean file from 28c8db4.
• err.rs — removed a duplicate ReplayedOverride; added 6 declared-nowhere variants;
  catch-all arms on description() / code().
• storage.rs — removed a duplicate AdminOverrideNonce; added PlaceBetsIdem and
  AntiGriefFloor.
• gas.rs — Env::budget() is test-only, so BudgetGuard degrades to a no-op outside
  tests; fixed an oversized symbol_short! and an invalid Default derive.
• upgrade_manager.rs — fixed a u32/u64 branch mismatch.

Auth matrix

Entrypoint	Subject	Verified by
create_market, resolve_market_manual, collect_fees, set_platform_fee, set_treasury, set_global_claim_period, set_market_claim_period, extend_deadline	admin	committed snapshot
sweep_unclaimed_winnings	admin	auth boundary
vote, place_bet, cancel_bet	user	committed snapshot
claim_winnings, dispute_market	user	auth boundary
get_market, get_market_bet_stats	none	committed snapshot

Committed snapshot — the call is driven through a fully satisfied happy path and the auth
is read back from env.auths(). Auth boundary — the host rolls back recorded auths when a
call traps or returns Err, so entrypoints needing state the fixture does not build assert
instead that an authorized call gets past require_auth while an unauthorized one traps.

API / visible changes

None. The suite is test-only, and the three fixes remove redundant authorization calls
without weakening any check.

Testing

cargo test -p predictify-hybrid --test auth_snapshot

test result: ok. 24 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out

cargo build -p predictify-hybrid --lib also succeeds, where it previously failed with ~40
parse and resolution errors.

Notes for reviewers

• Auth strength is unchanged — every removed call was a redundant second authorization
  within the same frame.
• Out of scope — several #[cfg(test)] modules under src/ still fail to compile from
  pre-existing API drift, and tests/err_stability.rs needs nightly (variant_count).
• Local Windows builds hit a MinGW export ordinal too large link error on the cdylib
  when testutils is enabled; run locally with crate-type = ["lib"]. Linux CI is
  unaffected.