[CloudCorpRecords]

Issue #, if available: #5256

Description of changes:
The JavaScript highlight rules already tokenized digit separators in the mantissa and in hex, octal, and binary literals, but the exponent part of the decimal rule only accepted plain digits. That split literals like 1e1_0 into a numeric token plus an identifier. This change allows separators in the exponent digits, using the same digit-plus-separator pattern the mantissa already uses, so 1e1_0, 1_000e1_0, .5_5e1_0, and 1E+1_0 each tokenize as one constant.numeric token. The PHP rules already handled separators, including exponents, so no PHP change was needed.

Tests run:

• src/mode/javascript_test.js: 20 passed, 1 pre-existing skip, including a new tokenizer test covering the exponent cases plus mantissa and plain-exponent regressions. The new test fails on the base commit and passes with the fix.
• src/mode/php_test.js: 1 passed.
• src/mode/html_test.js and src/mode/coldfusion_test.js (both import the JavaScript rules): 2 passed each.

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

Pull Request Checklist:

• No backwards incompatible changes were made to Ace's public interface which is defined through the main typings file (ace.d.ts) and its references: no typings files were changed.

Open kitchen-sink @ 3498664f50183e41276c22d8451c11931615c5be