Fix filteredViewTotals and chartAggregations to use per-transaction tags

[Copilot]

Both filteredViewTotals and chartAggregations were hoisting merchant.tags (the union of all tags across every transaction in that merchant entry) outside the transaction loop, causing categorizeAmount() to misclassify transactions that individually carry only a subset of those tags. This produces a mismatch between the Filtered View KPI card and the Cash Flow KPI card (which Python precomputes per-transaction).

Changes

• filteredViewTotals — removed outer const tags = merchant.tags || []; replaced categorizeAmount(txn.amount, tags) with categorizeAmount(txn.amount, txn.tags || [])
• chartAggregations — same fix: dropped merchant-level tags variable, pass txn.tags || [] directly

// Before — all txns in a merchant share the aggregate tag union
const tags = merchant.tags || [];
for (const txn of txns) {
    const c = categorizeAmount(txn.amount || 0, tags);

// After — each txn is classified by its own tags
for (const txn of txns) {
    const c = categorizeAmount(txn.amount || 0, txn.tags || []);

Each transaction already carries its own tags array in the report JSON, so no data-shape changes are required.