docs: auto-update tree-sitter accuracy data

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Automated update from the latest tree-sitter accuracy measurement on main.

Notable changes since the previous batch

• tcl Args Exact-Match improved 16.2pp (83.8% → 100.0%)

• dart Func Precision improved 6.4pp (65.7% → 72.1%)

• Appends one row per language to docs/self_scan/tree_sitter_accuracy_history.csv.

• Regenerates the summary table in gitgalaxy/standards/language_standards.py.

• Re-renders docs/self_scan/tree_sitter_accuracy_chart.svg from that same batch.

Never touches tests/tree_sitter_accuracy_baseline_*.json -- those stay
human-reviewed via tree_sitter_accuracy_audit.py --regenerate.

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Closing as stale/conflicted -- this scan ran against dart's merge (#1538) commit before tcl's fix (#1539) landed a minute later, so its own numbers don't include the tcl improvement its own summary claims, and it now conflicts with main's own auto-update (1252180) which has the same staleness. Rather than hand-resolve generated-file conflicts, letting the next merge-triggered run regenerate this fresh and non-conflicting once the current batch of sweep PRs (#1538/#1539 landed, csharp-1427/python-1527/golden-master-bless still in flight) settles.