fix(components): paint table columns at their measured widths

[LeadcodeDev]

Severity Medium, category correctness. Location: crates/rustmotion-components/src/table.rs:116

Impact

TableIntrinsic::compute_width (intrinsic.rs:911-949) measures every header and every cell, keeps a per-column max (col_widths[i] = col_widths[i].max(w + cell_padding * 2.0)) and returns the sum. The painter then throws that per-column distribution away and gives each column total_w / col_count. For an uneven table (e.g. headers ["ID", "Description of the incident"], natural widths 60px and 400px → intrinsic 460px) the painter allocates 230px per column; the 400px column's text is drawn from align_text_x at a position computed against a 230px cell and there is no per-cell clip (table.rs:203-262 draws each cell with draw_text_with_fallback and only advances col_x += cw), so the text overlaps the neighbouring column or spills past the table's right edge. With column_align: "right" it spills backwards into the previous column. The measurer's own doc comment (intrinsic.rs:884-888) asserts the opposite: "Natural size formula (matches the painter exactly) ... otherwise each column gets max(header_text_width + 2 × cell_padding, min_col_width)" — the painter implements no such rule, and compute_width has no min_col_width either.

Fix

Extract the per-column width computation into one function on Table (returning Vec<f32>), have TableIntrinsic sum its result and resolve_column_widths return it directly, scaling proportionally when the laid-out width differs from the natural one. Fix the now-false doc comment at intrinsic.rs:884.

Evidence the audit read

fn resolve_column_widths(&self, total_w: f32) -> Vec<f32> {
        let col_count = self.headers.len().max(1);
        if let Some(widths) = &self.column_widths {
            ...
        } else {
            vec![total_w / col_count as f32; col_count]
        }
    }

Stacked on fix/cascade-reaches-painters, which carries the previous finding of this workstream. GitHub shows only this finding's diff; merge in order.

Part of the September 2026 audit remediation chantier. Refs #220 (RM-08).