stdlib: expand compatibility foundations

[youknowone]

Summary

• expand the stdlib compatibility foundation across functools, inspect, typing/generic aliases, symtable, tokenize, time, _sre, and pickle
• restore PyPy-shaped pickle reconstruction semantics for REDUCE, NEWOBJ/NEWOBJ_EX, BUILD, memo persistence, EOFError, UTF-8 diagnostics, and re-entrancy
• root moving-GC-sensitive owners and transient values across callbacks and allocations
• preserve process-global descriptor/type identity and JIT exception type registration
• pin the separately maintained RustPython Windows host_env fix

Validation

• python3 scripts/extract-llbc.py
• PYRE_RTYPER_VERBOSE=1 cargo build --release -p pyre-jit-trace
• cargo fmt --all -- --check
• cargo check --features dynasm
• cargo test --features dynasm
• dynasm pre-merge benchmark/output suite: 14/14 passed
• JIT-enabled functools/pickle/typing parity regressions passed
• test_typing: 709 passed, 2 skipped
• test_inspect: 361 passed, 43 skipped; the existing pure-Python _datetime member-descriptor mismatch remains
• test_functools: placeholder regression fixed; the two pre-existing recursion-depth cases remain
• test_pickle: the former native crash is fixed; PyPy's literal BUILD dict.update structure intentionally exposes four CPython-only exception-type expectation differences

RustPython dependency

The only RustPython-side change is isolated in ../RustPython2 and pinned by revision: the Windows host_env rename compatibility fix (6d5cf573788ca045bd697fa1e45f6734567574bc). No stdlib semantic changes were made there.