refactor: extract ParseBlock/ParseExprList, resync-based error recovery

Seven copy-pasted statement-block loops collapse into
ParseBlock(terminators); five comma-separated expression-list loops
collapse into ParseExprList(close, allowEmpty), which also fixes
"arr[1 2] <- x" being silently accepted as arr[1,2] on the statement
path. Error recovery now lives in one place: syncToStatementStart skips
to the next statement-start/block-end token, so a bad statement no
longer swallows the first token of the following good one. Drop the
dead -1000/-1001 token check in ParsePrototypeArgs.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

0 files changed, 0 insertions, 0 deletions