This closes #2303, add File.Recalc for whole-workbook recalc

[krystophny]

Description

Add (*File).Recalc() error, built on top of RecalcCell from the companion PR #2311. Recalc walks every formula cell in the workbook, calls RecalcCell on each, and returns an errors.Join-aggregated error listing any per-cell failures wrapped as "<sheet>!<cell>: <cause>". Cells that did compute are still persisted when later cells fail.

Public surface introduced by this PR:

• (*File).Recalc() error

No existing API is changed or removed.

Related Issue

Closes umbrella #2303. Depends on #2311 (introduces RecalcCell); this PR's branch is stacked on that PR's branch so CI runs against the combined state. It will rebase cleanly on master once #2311 merges.

Documentation

Reference-site entries for this PR ship in a companion docs PR: xuri/excelize-doc#31. That PR covers the English version; other language versions follow the project's usual rollout cadence.

Motivation and Context

Users who open a workbook, mutate inputs, and save it back currently have no way to refresh the cached values downstream consumers rely on. CalcCellValue returns a formatted string but does not persist it, and every SetCell* writer removes the formula while writing a new value, which makes them useless for this purpose. The result is that LibreOffice-headless, Numbers, and other readers that trust <v> without recomputing see stale results after a round trip through excelize. Recalc closes that gap with a single entry point and zero cost to callers who do not use it.

Design notes reviewers are likely to ask about:

• Fixed-point iteration. Not needed. calcCellValue already recurses into referenced cells during evaluation, so a single pass converges chained dependencies across sheets. The calc cache is cleared before and after the sweep to avoid cross-call contamination.
• Error model. Failures never abort the pass. Each failure is fmt.Errorf("<sheet>!<cell>: %w", cause); the collection is returned via errors.Join(...). Callers descend with errors.Is / errors.As through the standard Unwrap() []error method the joined error provides. This replaces the typed RecalcError / RecalcCellError surface that an earlier draft proposed — no new exported error types are added here.

Scoping via a RecalcOptions{Sheet, Ref} value is intentionally deferred to #2308 so this PR keeps the API surface minimal; the zero-option form covers the umbrella's stated requirement.

How Has This Been Tested

$ go test -run 'TestRecalc' -timeout 60s -v .
=== RUN   TestRecalcCellTypes
--- PASS: TestRecalcCellTypes (0.00s)
=== RUN   TestRecalcCellNoFormula
--- PASS: TestRecalcCellNoFormula (0.00s)
=== RUN   TestRecalcCellNoTypeSRegression
--- PASS: TestRecalcCellNoTypeSRegression (0.00s)
=== RUN   TestRecalcCellSharedFormulaBand
--- PASS: TestRecalcCellSharedFormulaBand (0.00s)
=== RUN   TestRecalcCellCircularReferenceBounded
--- PASS: TestRecalcCellCircularReferenceBounded (0.00s)
=== RUN   TestRecalcCellRoundTrip
--- PASS: TestRecalcCellRoundTrip (0.00s)
=== RUN   TestRecalcChainedAcrossSheet
--- PASS: TestRecalcChainedAcrossSheet (0.00s)
=== RUN   TestRecalcIdempotent
--- PASS: TestRecalcIdempotent (0.00s)
=== RUN   TestRecalcWorkbookWithoutFormulas
--- PASS: TestRecalcWorkbookWithoutFormulas (0.00s)
=== RUN   TestRecalcAggregatesFailures
--- PASS: TestRecalcAggregatesFailures (0.00s)
=== RUN   TestRecalcNonASCIISheetName
--- PASS: TestRecalcNonASCIISheetName (0.00s)
PASS
ok  	github.com/xuri/excelize/v2	0.014s

Full suite: go test -skip TestZip64 -timeout 10m . passes cleanly. gofmt -s -l . and go vet ./... are clean. ARM cross-builds (GOARM=5|6|7, arm64, android/arm64) all build.

Types of changes

• Docs change / refactoring / dependency upgrade
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly (see companion docs PR Update en version docs for File.Recalc, RecalcCell, RecalcOptions, ErrCellNoFormula, and 3D range support xuri/excelize-doc#31).
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Documentation for the new exported surface lives in the doc comment on Recalc.