Return an empty string when trimq receives empty/fully-trimmed input.
Also normalize ctype usage with unsigned-char casts in trim helpers.

When parse_prefix returns nil and strict_parse is disabled, record the invalid line and continue.
This avoids later nil-prefix transition handling crashes in validation flows.

Only decrement branch_valid once per IF condition evaluation.
Multiple failed asserts in the same IF no longer corrupt branching state.

Introduce parser.max_statements defaulting to 1,000,000 executed statements.
Abort execution when the budget is exceeded to reduce loop-based DoS impact.

Clear AST and control-flow runtime fields before each begin.
This prevents stale state reuse across executions in persistent Lua VM contexts.

Add normalize_stmt() in C and use it from set_sentence.
Preserves normalization semantics while reducing repeated Lua gsub overhead.

Replace heap allocation with a fixed MAX_LINE stack buffer and reject oversized lines.
Return explicit parser errors for normalization limits instead of silent nil fallbacks.

Use C parse_prefix for blank/comment detection and feed raw lines to callbacks.
Normalize_stmt now trims edges internally to preserve matching semantics.

Skip gmatch setup when a matched statement has no single quotes.
This avoids iterator overhead on common no-argument statements.

Keep parse-loop no-trim optimization, but trim ctx.msg in set_sentence.
This restores stable runtime error lines expected by JS decode_error tests.