When computing taxes for invoice lines, the system should use the `invoice_label` field instead of the default `name` field to display tax information. This allows invoices to show more appropriate tax labels that may differ from the internal tax name.

Technical details:
- Added `is_invoice` context when calling `tax_ids.compute_all()` in `account.move.line._compute_all_tax()` method
- Modified `account.tax.compute_all()` to check for `is_invoice` context and select appropriate field name (`invoice_label` for invoices, `name` for other documents)
- The selected field name is used when building the tax values dictionary
  returned by `compute_all()`

This change ensures that invoice tax lines display the correct label as defined in the tax's `invoice_label` field, which is particularly useful for localized tax reporting requirements where the invoice label may differ from the internal tax name.


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