Fix BigDecimalLiteralDouble for boxed floating-point values

[codingkiddo]

Fixes #5759.

Summary

BigDecimalLiteralDouble reported precision-loss diagnostics for direct double / float literals passed to BigDecimal(double), but it missed boxed Double / Float values.

For example:

Double boxedD = 0.1;
new BigDecimal(boxedD);

This still invokes the BigDecimal(double) constructor after unboxing, so it has the same precision-loss problem as passing a primitive floating-point literal directly.

Changes

• Added regression coverage for boxed Double / Float arguments.
• Updated BigDecimalLiteralDouble to detect boxed floating-point arguments consistently with primitive floating-point arguments.
• Kept the existing suggested fix behavior limited to direct literal cases, where the replacement source is safe to construct.

Test

mvn -pl core -Dtest=BigDecimalLiteralDoubleTest test

Result:

Tests run: 3, Failures: 0, Errors: 0, Skipped: 0
BUILD SUCCESS

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