Add complete Python 3.14 support with loop/exception handling hardening

[zsy-arch]

Bytecode & module layer:

• Python 3.14 magic numbers and bytecode table (bytecode_ops.inl), bytes/python_3_14.cpp; opcode handling in bytecode.cpp/data.h for CALL_KW, LOAD_CONST folding, RETURN_CONST, JUMP_BACKWARD loops, exception-table (zero-cost try) landing pads.
• pyc_module/pyc_object: marshal parsing for 3.14 code objects.

ASTree structural reconstruction:

• Prescan-driven while True: recognition for 3.9+ (no SETUP_LOOP): unconditional-loop heads from JUMP_BACKWARD targets, with rotated-loop condition-head rejection (mid-body conditional exit + protected_cycle exception-entry guard) so rotated inner while loops (quicksort-style) are not misdetected.
• 3.13/3.14 while-try-finally with continue: handler back-edge targets the condition-evaluation head; finally rendered on both normal and exception paths; deferred in-loop handler containers (pending_conts) with nested-try support.
• while-else exit transform via JUMP_BACKWARD; dangling WHILE closed on RETURN_VALUE at EOF; EOF-guarded dead-jump probes for both RETURN_VALUE and RETURN_CONST; curpos kept at current-opcode semantics (fixes 3.10 module-level for RETURN duplication and 3.9 yield_from spurious return None).
• PEP 709 inline-comprehension bookkeeping resets.

Tests (tests/py314_roundtrip):

• Closed-loop roundtrip runner (compile -> pycdc -> ast.parse -> test probe equivalence) with interpreter autodetection, 21 cases x {3.13, 3.14} including nested loop/exception shapes, algorithms (quicksort, sieve, RC4), tree/graph (BST/BFS/DFS).
• Validation: roundtrip 42/42, upstream suite 0 FAIL (93 PASS/XFAIL), semantic probe matrix 8/8.