chore(deps): bump bignumber.js from 9.1.2 to 11.1.1 in /backend

[dependabot]

Bumps bignumber.js from 9.1.2 to 11.1.1.

Release notes

Sourced from bignumber.js's releases.

v11.1.0 adds a few useful improvements around formatting, parsing, rounding, and interoperability.

BigNumber.sum() now returns zero when called with no arguments, which makes patterns like BigNumber.sum(...arr) work cleanly even when the array is empty.

BigNumber.sum(...[]).toString()      // "0"

toBigInt() has been added, so BigNumber values can now be converted directly to native BigInt values.

new BigNumber("123.9").toBigInt(BigNumber.ROUND_DOWN)        // 123n

There is also a new BigNumber.fromFormat() method for parsing formatted strings back into BigNumber values.

const options =  {  prefix: "€",  groupSeparator: ".",  decimalSeparator: "," }
BigNumber.fromFormat("€1.234.567,89", options).toString()      // "1234567.89"

Negative decimal places are now supported by decimalPlaces(), toFixed(), and toFormat(), making it easier to round to tens, hundreds, and thousands etc.

new BigNumber("1234.5").toFormat(-2)      // "1,200"

toFormat() has also been expanded to support minimum and maximum decimal places, and per-call formatting options now fall back to the configured global FORMAT values for anything not explicitly overridden.

new BigNumber("12.3456789").toFormat([2, 5])      // "12.34568"

This release also includes a fix for slow hexadecimal integer base conversion when DECIMAL_PLACES is very large, plus improved TypeScript API test coverage.

Changelog

Sourced from bignumber.js's changelog.

11.1.1

• 02/05/26
• Docs: fix version number and decimalPlaces API description.

11.1.0

• 30/04/26
• #401 BigNumber.sum: return zero if there are no arguments.
• #352 Add toBigInt method.
• #286 Add fromFormat method.
• #262 decimalPlaces, toFixed and toFormat: support negative decimal places.
• #260 toFormat: support minimum/maximum decimal places.
• toFormat: fallback to FORMAT for each property not in options.
• [BUGFIX] #342 Large DECIMAL_PLACES causing slow hex integer base conversion.
• Typescript: add test_api.ts to improved typed API test coverage.

11.0.0

• 14/04/26
• Add STRICT configuration option: if true (default), throw an exception on invalid input. if false, return NaN on invalid input.
• toFraction: return [1, 0] for Infinity and [0, 0] for NaN.
• Support underscores as separators.
• If a base is supplied, reject non-finite values and base prefixes.

10.0.2

• 24/02/26
• Reinstate README.md links.

10.0.1

• 24/02/26
• Commit dist folder.

10.0.0

• 23/02/26
• Implement targeted builds for ES modules, CommonJS, and browser (global assignment).
• Add CI workflow.
• Add type declaration import tests.
• Remove BigNumber.DEBUG, so the behaviour is now always as if it was true: throw on invalid input instead of returning NaN, and always validate the c, e, and s properties of objects passed to isBigNumber
• Don't call toString on any arbitrary object passed to the constructor.
• Require a BigNumber value to be a string if a base is also passed.
• Add toObject prototype method which returns a plain object with c, e, and s properties.
• Remove .npmignore, as files in package.json is used. Add .gitignore.

... (truncated)

Commits

• 1e55b9a v11.1.1
• 300e0f3 docs: fix decimalPlaces API description
• cca72ee Update version number in API.html
• 2f0e7de v11.1.0
• e06dfc2 Implement fromFormat. toFormat: support [min, max] decimal places.
• 128ad3a #262 decimalPlaces: accept a negative decimal places count.
• 85482a3 #352 Add toBigInt method.
• aa2cfdb BigNumber.sum: return zero if there are no arguments
• 1b09c08 v11.0.0
• aceb0d2 Support underscores as separators. Refactor constructor.
• Additional commits viewable in compare view

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