Adds control flow, field access, forward self calls, method/program entry tracking, and E227 emission-failure reporting. Print vectors now live in safe zero-page cells to avoid the 6502 indirect-JMP page bug.

Statement emission now runs from parser pass 2: assignment, byte + and -, and
print reach codegen.s through emit.s, and the statements fixture executes the
emitted bytes in x128. Restoring the parser trace fixture's length arithmetic
(it emitted between the two halves of the subtraction, which clears carry)
brings the 41-fixture parser verification back to green after emit.s joined
the link.

Also check in the vim clone's improved C128 build and the Power C
reverse-engineering notes and tools.

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Co-Authored-By: Codebuff <noreply@codebuff.com>