[WIP] Partial SSA for decompilation

[ltfish]

TODOs:

• [ ] TSSA -> CSSA conversion (test cases: test_df_add_uint_with_neg_flag_ite_expressions, test_loop_counter_reg)
• [ ] Phi-assignment-aware statement and expression comparison.
• [ ] Fix SAILR support.
• [ ] Fix function inlining support.
• [ ] Improve Clinic's decompilation progress percentage calculation: Use deltas instead of absolute numbers.
• [ ] Function parameter narrowing.