fix(optimizer): correct semantic classification of TRON instructions

[yanghang8612]

Summary

libevmasm/SemanticInformation.cpp mis-classifies several TRON-specific instructions for the optimizer. The most serious is a Critical miscompilation on the via-IR pipeline.

Fixes

• NATIVEFREEZEEXPIRETIME was treated as movable (Critical). It reads an address's stake expire-time — state that NATIVEFREEZE/NATIVEUNFREEZE mutate — but with sideEffects=false and no entry in the movable() / movableApartFromEffects() whitelists it fell through to "movable". The Yul CSE/LICM then reuses a cached freezeExpireTime value across an intervening freeze write, reading stale data. Added it to both whitelists (alongside TOKENBALANCE).
• ISCONTRACT was missing from movableApartFromEffects() and isDeterministic(). It is the same family as EXTCODESIZE / TOKENBALANCE; added so it is optimized correctly and not over-conservatively.
• NATIVEVOTE in readWriteOperations(): the memory-read length was the array element count rather than a byte length, which could let UnusedStoreEliminator drop the array writes. Changed to a conservative unknown-length read, and added a paramCount >= 4 guard before the size_t subtractions.
• Removed the unreachable return true; after the movable() switch.

Verification

• solc builds cleanly.
• With --experimental-via-ir --optimize, NATIVEFREEZEEXPIRETIME (0xd7) is now emitted twice across a freeze write (previously CSE collapsed it to one). vote and ordinary contracts still compile on both the legacy and via-IR pipelines.

Targets release_0.8.28.

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