feat: swap chart panel positions — bar chart needs wide column, donut fits narrow

[pitimon]

Problem

Current layout puts the bar chart in a narrow column and donut in a wide-capable position:

Row 1: [TOKEN USAGE OVER TIME (wide)]  [PROJECT ACTIVITY bar (narrow)]
Row 2: [PEAK HOURS (wide)]             [MODEL DISTRIBUTION donut (narrow)]

After #130 changed PROJECT ACTIVITY from donut to horizontal bar chart, it needs more horizontal space for labels + bars. Currently bars are compressed and project names get truncated.

MODEL DISTRIBUTION (donut) is compact by nature — works fine in a narrow column.

Suggested Layout

Option A — Swap row 1 positions:

Row 1: [TOKEN USAGE OVER TIME (wide)]  [MODEL DISTRIBUTION donut (narrow)]
Row 2: [PROJECT ACTIVITY bar (wide)]   [PEAK HOURS (narrow)]

• Bar chart gets the wide column — labels readable, bars proportional
• Donut fits naturally in narrow space
• Peak hours is compact (24 small bars) — works in narrow column

Option B — Minimal swap (same rows):

Row 1: [TOKEN USAGE OVER TIME (wide)]  [MODEL DISTRIBUTION donut (narrow)]
Row 2: [PEAK HOURS (wide)]             [PROJECT ACTIVITY bar (narrow)]

• Only swaps the two right-column charts
• Less layout disruption, but bar chart still narrow

Recommend Option A — gives bar chart the wide column it needs.

Implementation

Swap the chart components in app/overview-client.tsx grid layout (~line 275-290).

Context

• PROJECT ACTIVITY changed from donut to bar chart in feat: improve chart professionalism — bar chart for projects, enhanced donut for models #130
• Bar chart with 8 project names needs ~400px+ width for readable labels
• Related: feat: improve chart professionalism — bar chart for projects, enhanced donut for models #130 (chart types), feat: worktree grouping — compare UX between grouped vs ungrouped projects #135 (worktree grouping)

[pitimon]

Picking up Option A — swap positions: bar chart gets wide column, donut goes narrow.

[pitimon]

Resolved in PR #138.

• Row 1: Token usage (wide) + Model donut (narrow 320px)
• Row 2: Project bar chart (wide) + Peak hours (narrow 320px)
• Bar chart gets full width — project names readable without truncation