fix: redirect should consume exactly one destination

[fprochazka]

Summary

Fixes #233.

In bash, each redirect operator (>, <, >>, etc.) takes exactly one destination. The file_redirect rule previously used repeat1($._literal) which greedily consumed all subsequent tokens as redirect destinations.

This caused commands like grep 2>/dev/null -q "pattern" /etc/shells to incorrectly parse -q, "pattern", and /etc/shells as redirect destinations instead of command arguments.

Changes

• file_redirect: change repeat1($._literal) to $._literal (single destination)
• redirected_statement: allow argument fields after redirects so that tokens following a mid-command redirect are correctly preserved as arguments

Breaking changes

• file_redirect.destination is no longer multiple: true in node-types.json — it is now always a single node
• redirected_statement gains a new optional argument field for tokens that follow a mid-command redirect

Examples

Before (broken):

$ echo 'grep 2>/dev/null -q "pattern" /etc/shells' | tree-sitter parse
(redirected_statement
  (command (command_name (word)))       # grep
  (file_redirect (file_descriptor)
    (word) (word) (string) (word)))     # /dev/null -q "pattern" /etc/shells all as destinations

After (fixed):

(redirected_statement
  body: (command (command_name (word))) # grep
  redirect: (file_redirect
    (file_descriptor)
    destination: (word))               # only /dev/null
  argument: (word)                     # -q
  argument: (string)                   # "pattern"
  argument: (word))                    # /etc/shells

Test plan

• All 100 existing corpus tests pass (1 test expectation updated)
• Added regression test for find /path -name "*.sql" 2>/dev/null -exec grep -l "pattern" {} \;
• Verified edge cases: end-of-command redirects, heredocs, herestrings, backtick substitutions, test commands ([...]), pipes, compound statements, function definitions